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Wiki source code of 10 Communication Instruction

Version 3.1 by Iris on 2025/10/22 15:32
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1 == **Communication Port Protocol Setting** ==
2
3 ----
4
5 === **Communication port protocol setting** ===
6
7 ----
8
9 PROTOCOL(P)
10
11 Set (s) protocol for (n) communication port.
12
13 -[PROTOCOL (s) (n)]
14
15 Content, range and data type
16
17 |=**Parameter**|=**Content**|=**Range**|=**Data type**|=**Data type (label)**|=**Custom variable type**
18 |(s)|Protocol number to be set|-|Unsigned BIN16 bits|ANY16|INT
19 |(n)|Which communication port to be set, 0 means COM1, 1 means COM2|0, 1|Unsigned BIN16 bits|ANY16|INT
20
21 Device used
22
23 |=**Instruction**|=**Parameter**|=(% colspan="24" %)**Devices**|=**Index modification**|=**Pulse expansion**
24 | | |**X**|**Y**|**M**|**S**|**SM**|**T(bit)**|**C(bit)**|**LC(bit)**|**HSC(bit)**|**D.b**|**KnX**|**KnY**|**KnM**|**KnS**|**T**|**C**|**D**|**R**|**SD**|**LC**|**HSC**|**K**|**H**|**E**|**[D]**|**XXP**
25 |(% colspan="1" rowspan="2" %)PROTOCOL|Parameter 1| | | | | | | | | | | |●|●|●|●|●|●|●|●| | |●|●| |●|●
26 |Parameter 2| | | | | | | | | | | |●|●|●|●|●|●|●|●| | |●|●| |●|●
27
28 Function
29
30 This command is mainly used to set the protocol during RUN, and can also be used in the first cycle of RUN.
31
32 The value of the protocol address (COM1 SD2542, COM2 SD2592) and the protocol modification sign (COM1 SD2543, COM2 SD2593) can be directly set according to the command parameters.
33
34 The specific calculation formula for setting the protocol modification sign (COM1 SD2543, COM2 SD2593) is: (parameter setting value + offset of the corresponding serial port's initial special device+ 10)*2
35
36 For example, setting the protocol to 2, i.e. (2 +2593-2590 +10)*2, which is (2+3+10) *2=30. At this time, SD2592 will be set to 1, and SD2593 will be set to 32.
37
38 (% class="box infomessage" %)
39 (((
40 **✎Note: **
41
42 Whether the value is set by self-calculation and then modifying the identification (COM1 SD2543, COM2 SD2593) to the protocol, or by using this command, the protocol can be modified when the PLC is in the RUN state.
43
44 Protocol modification sign (COM1 SD2543 and COM2 SD2593): during the RUN process, when the protocol and modification sign are set correctly (the correctness will be judged at the End of the program), it will be deemed as the correct first cycle; then the protocol and modification sign (COM1 SD2543, COM2 SD2593) will be cleared upon completion of modification and the same value that is consequently set will not be processed. It mainly aims to avoid repeated settings for multiple times.
45 )))
46
47 Protocol number
48
49 |=**Protocol number**|=**Content**
50 |0H|Wecon Modbus slave station
51 |2H|Modbus RTU slave station
52 |3H|Modbus ASCII slave station
53 |10H|User-defined protocol
54 |20H|Modbus RTU master
55 |30H|Modbus ASCII master
56
57 Related devices
58
59 |=**Devices**|=**Content**
60 |SD2542|COM1 protocol settings
61 |SD2543|COM1 protocol modification sign
62 |SD2592|COM2 protocol settings
63 |SD2593|COM2 protocol modification sign
64
65 Precautions
66
67 The setting of communication parameters will affect the overall communication. The parameters in PLC are modified when there is no communication or after a round of communication is completed. Attention shall be paid to this point.
68
69 If the set protocol does not match the provided protocol number, the protocol modification flag (COM1 SD2543, COM2 SD2593) will not be cleared after setting. At this time, the protocol will not be set successfully, and it will run according to the original protocol.
70
71 Error code
72
73 |=**Error code**|=**Content**
74 |4085H|The read address (s) (n) exceeds the device range.
75 |4084H|(n) is not 1.
76
77 Example
78
79 (% style="text-align:center" %)
80 [[image:1709191890650-622.png]]
81
82 As shown in above example, M1 turns from OFF to ON during RUN process.
83
84 SD2594 will be set to 32 (20H), SD2595 will be set to 90 and then it will be cleared. At this time, it has been set successfully.
85
86 (% style="text-align:center" %)
87 [[image:1709191945171-155.png]]
88
89 If M1 turns from OFF to ON again,
90
91 SD2592 will be set to 32 (20H), SD2595 will be set to 90, which will not be cleared.
92
93 (% style="text-align:center" %)
94 [[image:1709191962952-895.png]]
95
96 == **Modbus Serial Port Parameter Setting** ==
97
98 ----
99
100 === **PORTPARA/Modbus serial port parameter setting** ===
101
102 ----
103
104 PORTPARA(P)
105
106 Set (s) serial port parameters for (n) communication port.
107
108 -[PORTPARA (s) (n)]
109
110 Content, range and data type
111
112 |=**Parameter**|=**Content**|=**Range**|=**Data type**|=**Data type (label)**|=**Custom variable type**
113 |(s)|Serial port parameters to be set|-|Unsigned BIN16 bits|ANY16|INT
114 |(n)|Which communication port to be set, 0 means COM1, 1 means COM2|0, 1|Unsigned BIN16 bits|ANY16|INT
115
116 Device used
117
118 |=**Instruction**|=**Parameter**|=(% colspan="24" %)**Devices**|=**Index modification**|=**Pulse expansion**
119 | | |**X**|**Y**|**M**|**S**|**SM**|**T(bit)**|**C(bit)**|**LC(bit)**|**HSC(bit)**|**D.b**|**KnX**|**KnY**|**KnM**|**KnS**|**T**|**C**|**D**|**R**|**SD**|**LC**|**HSC**|**K**|**H**|**E**|**[D]**|**XXP**
120 |(% colspan="1" rowspan="2" %)PORTPARA|Parameter 1| | | | | | | | | | | |●|●|●|●|●|●|●|●| | |●|●| |●|●
121 |Parameter 2| | | | | | | | | | | |●|●|●|●|●|●|●|●| | |●|●| |●|●
122
123 Function
124
125 This command is mainly used to set serial port parameters during RUN, and can also be used in the first cycle of RUN.
126
127 The value of serial port parameter address (COM1 SD2540, COM2 SD2590) and the serial parameter modification sign (COM1 SD2541, COM2 SD2591) can be set directly according to the command parameters.
128
129 The specific calculation formula for setting the serial port parameter modification sign (COM1 SD2541, COM2 SD2591) is: (parameter setting value + offset of the corresponding serial port's initial special device + 10)*2
130
131 For example, setting the COM1 serial port parameter to 193 (HC1), i.e. (193 +2541-2540 +10)*2 which is (193 +1+10) *2=408. At this time, SD2540 is set to be 193(HC1) and SD2541 is set to be 408.
132
133 (% class="box infomessage" %)
134 (((
135 **✎**Note:
136
137 Whether the value is set by self-calculation and then modifying the sign (COM1 SD2541, COM2 SD2591) to the serial port parameters, or by using this command, the serial port parameters can be modified when the PLC is in the RUN state.
138
139 Serial port parameter modification sign (COM1 SD2541 and COM2 SD2591): during the RUN process, when the serial port parameter and modification sign are set correctly (the correctness will be judged at the End of the program), it will be deemed as the correct first cycle; then the serial port parameter and modification sign (COM1 SD2541, COM2 SD2591) will be cleared upon completion of modification and the same value that is consequently set will not be processed. It mainly aims to avoid repeated settings for multiple times.
140 )))
141
142 Serial port parameter setting table
143
144 |=**Bit number**|=**Name**|=(% colspan="2" %)**Content**
145 | | |**0 (bit OFF)**|**1 (bit ON)**
146 |b0|Data length|7 digits|8 digits
147 |(((
148 b1
149
150 b2
151 )))|Parity check|(% colspan="2" %)(((
152 b2, b1
153
154 (0, 0): None
155
156 (0,1): Odd parity (ODD)
157
158 (1,1): Even parity (EVEN)
159 )))
160 |b3|Stop bit|1 bit|2 bit
161 |(((
162 b4
163
164 b5
165
166 b6
167
168 b7
169
170 b8
171
172 b9
173 )))|Baud rate(bps)|(((
174 .b9,b8,b7,b6,b5,b4
175
176 ( 0, 0, 0, 1, 1, 1): 4800
177
178 ( 0, 0, 1, 0, 0, 0): 9600
179
180 ( 0, 0, 1, 0, 0, 1): 19200
181
182 ( 0, 0, 1, 0, 1, 0): 38400
183
184 ( 0, 0, 1, 0, 1, 1): 57600
185 )))|(((
186 .b9,b8,b7,b6,b5,b4
187
188 ( 0, 0, 1, 1, 0, 0): 115200
189
190 ( 0, 0, 1, 1, 0, 1): 187500
191
192 ( 0, 0, 1, 1, 1, 0): 230400
193
194 ( 0, 0, 1, 1, 1, 1): 460800
195
196 ( 0, 1, 0, 0, 0, 0): 921600
197 )))
198 |b10|STX|Disable STX function|Enable STX function, the specific value is set by D8124
199 |b11|ETX|Disable ETX function|Enable the ETX function, the specific value is set by D8125
200 |b12|~-~-|~-~-|~-~-
201 |b13|~-~-|~-~-|~-~-
202 |b14|~-~-|~-~-|~-~-
203 |b15|~-~-|~-~-|~-~-
204
205 Related devices
206
207 |=**Devices**|=**Content**
208 |SD2540|COM1 serial port parameter setting
209 |SD2541|COM1 serial port parameter modification sign 
210 |SD2590|COM2 serial port parameter setting
211 |SD2591|COM2 serial port parameter modification sign
212
213 Precautions
214
215 The setting of communication parameters will affect the overall communication. The parameters in PLC are modified when there is no communication or after a round of communication is completed. Attention shall be paid to this point.
216
217 STX function and ETX function are only useful in the case of user-defined protocol.
218
219 If the set protocol does not match the provided protocol number, the serial port parameter modification sign (COM1 SD2541, COM2 SD2591) will not be cleared after setting. At this time, the protocol will not be set successfully, and it will run according to the original protocol.
220
221 Error code
222
223 |=**Error code**|=**Content**
224 |4085H|The read address (s) and (n) exceeds the device range.
225 |4084H|(n) is not 0 or 1.
226
227 Example
228
229 (% style="text-align:center" %)
230 [[image:1709192341229-210.png]]
231
232 As shown in the above example,
233
234 M1 turns from OFF to ON during RUN process.
235
236 SD2540 will be set to 129 (H81, baud rate: 9600, stop bit: 1, data bit: 8, parity bit: none), SD2541 will be set to 280 and then cleared. At this time, it has been set successfully.
237
238 (% style="text-align:center" %)
239 [[image:1709192357577-580.png]]
240
241 If M1 turns from OFF to ON again,
242
243 SD2540 will be set to 129 (H81), SD2541 will be set to 280, which will not be cleared.
244
245 (% style="text-align:center" %)
246 [[image:1709192373970-129.png]]
247
248 == **Modbus Station Number Setting** ==
249
250 ----
251
252 === **STATION/Modbus station number setting** ===
253
254 ----
255
256 STATION (P)
257
258 Under the Modbus slave station protocol. Set the station number (s) for the (n) communication port.
259
260 -[STATION (s) (n)]
261
262 Content, range and data type
263
264 |=**Parameter**|=**Content**|=**Range**|=**Data type**|=**Data type (label)**|=**Custom variable type**
265 |(s)|Station number to be set|0~~255|Unsigned BIN16 bits|ANY16|INT
266 |(n)|Which communication port to set, 0 means COM1, 1 means COM2|0, 1|Unsigned BIN16 bits|ANY16|INT
267
268 Device used
269
270 |=**Instruction**|=**Parameter**|=(% colspan="24" %)**Devices**|=**Index modification**|=**Pulse expansion**
271 | | |**X**|**Y**|**M**|**S**|**SM**|**T(bit)**|**C(bit)**|**LC(bit)**|**HSC(bit)**|**D.b**|**KnX**|**KnY**|**KnM**|**KnS**|**T**|**C**|**D**|**R**|**SD**|**LC**|**HSC**|**K**|**H**|**E**|**[D]**|**XXP**
272 |(% colspan="1" rowspan="2" %)STATION|Parameter 1| | | | | | | | | | | |●|●|●|●|●|●|●|●| | |●|●| |●|●
273 |Parameter 2| | | | | | | | | | | |●|●|●|●|●|●|●|●| | |●|●| |●|●
274
275 Function
276
277 This command is mainly used to set the station number during RUN, and can also be used in the first cycle of RUN.
278
279 * (((
280 The value of the station number address (COM1 SD2544, COM2 SD2594) and the station number modification sign (COM1 SD2545, COM2 SD2595) can be directly set according to the command parameters.
281 )))
282 * (((
283 The specific calculation formula for setting the station number modification sign (COM1 SD2545, COM2 SD2595) is: (parameter setting value + offset of the corresponding serial port's initial special device + 10) *2
284 )))
285
286 For example, setting COM2 station number to 1, i.e. (1 +2595 - 2590 +10) *2, which is (1 +5+10) *2=32. At this time, SD2594 will be set to 1, and SD2595 will be set to 32.
287
288 Note: Whether the value is set by self-calculation and then modifying the sign (COM1 SD2545, COM2 SD2595) to the station number, or by using this command, the station number can be modified when the PLC is in the RUN state.
289
290 Station number modification sign (COM1 SD2545 and COM2 SD2595): During RUN, when the station number and modification sign are set correctly (the correctness will be judged at the End of the program), it will be deemed as the correct first cycle; then the protocol and modification sign (COM1 SD2545, COM2 SD2595) will be cleared upon completion of modification and the same value that is consequently set will not be processed. It mainly aims to avoid repeated settings for multiple times.
291
292 Related devices
293
294 |=**Devices**|=**Content**
295 |SD2544|COM1 station number settings
296 |SD2545|COM1 station number modification sign 
297 |SD2594|COM2 station number settings
298 |SD2595|COM2 station number modification sign
299
300 Error code
301
302 |**Error code**|**Content**
303 |4085H|The read address (s) (n) exceeds the device range.
304 |(% colspan="1" rowspan="2" %)4084H|(s) not within the range of 0~~255.
305 |(n) is not 0 or 1.
306
307 Precautions
308
309 The setting of communication parameters will affect the overall communication. The parameters in PLC are modified when there is no communication or after a round of communication is completed. Attention shall be paid to this point.
310
311 Example
312
313 (% style="text-align:center" %)
314 [[image:1709192619027-553.png]]
315
316 As shown in the above example,
317
318 M1 turns from OFF to ON during RUN process.
319
320 SD2594 will be set to 2, SD2595 will be set to 34 and then it will be cleared. At this time, it has been set successfully.
321
322 (% style="text-align:center" %)
323 [[image:1709192635876-596.png]]
324
325 If M1 turns from OFF to ON again,
326
327 SD2594 will be set to 2, SD2595 will be set to 34 but will not be cleared.
328
329 (% style="text-align:center" %)
330 [[image:1709192654323-459.png]]
331
332 == **RS Instruction** ==
333
334 ----
335
336 === **RS/External communication command** ===
337
338 ----
339
340 RS
341
342 In Modbus master station protocol: the command is the setting interface for the master station to send protocol frames. According to the station number function code (s), slave station address (m), length (d) set by the command and the function code, it can be determined whether n data is required to automatically combine the transmission and reception of protocol frames. If it is a read type function code, the data will be written into (n).
343
344 -[RS (s) (m) (d) (n)]
345
346 Content, range and data type
347
348 |=**Parameter**|=**Content**|=**Range**|=**Data type**|=**Data type (label)**|=**Custom variable type**
349 |(s)|The starting address of the register area where the data to be sent is stored.|-|Unsigned BIN16 bits|ANY16|~-~-
350 |(m)|The length (in bytes) of the data to be sent.|0~~523|Unsigned BIN16 bits|ANY16|~-~-
351 |(d)|The starting number of the device that stores written data.|-|Unsigned BIN16 bits|ANY16|~-~-
352 |(n)|Volume of data written (in bytes).|0~~523|Unsigned BIN16 bits|ANY16|~-~-
353
354 In Modbus protocol:
355
356 |=**Parameter**|=**Content**|=**Range**|=**Data type**|=**Data type (label)**
357 |(s)|The high byte stores the station number of the slave station, and the low byte stores the Modbus function code.|-|Unsigned BIN16 bits|ANY16
358 |(m)|Slave station address. The address provided by the slave station will read or write data from the address of slave station.|-|Unsigned BIN16 bits|ANY16
359 |(d)|Length, the data length read or written by Modbus, and the unit are determined by the function code.|-|Unsigned BIN16 bits|ANY16
360 |(n)|The starting address for data to be read or written.|-|Unsigned BIN16 bits|ANY16
361
362 Device used
363
364 |=**Instruction**|=**Parameter**|=(% colspan="24" %)**Devices**|=**Index modification**|=**Pulse expansion**
365 | | |**X**|**Y**|**M**|**S**|**SM**|**T(bit)**|**C(bit)**|**LC(bit)**|**HSC(bit)**|**D.b**|**KnX**|**KnY**|**KnM**|**KnS**|**T**|**C**|**D**|**R**|**SD**|**LC**|**HSC**|**K**|**H**|**E**|**[D]**|**XXP**
366 |(% colspan="1" rowspan="4" %)RS|Parameter 1| | | | | | | | | | | | | | |●|●|●|●| | | |●|●| | |
367 |Parameter 2| | | | | | | | | | | | | | |●|●|●|●| | | |●|●| | |
368 |Parameter 3| | | | | | | | | | | | | | |●|●|●|●| | | |●|●| | |
369 |Parameter 4| | | | | | | | | | | | | | |●|●|●|●| | | |●|●| | |
370
371 User-defined protocol
372
373 When the communication protocol is set as a user-defined protocol. When the contact in front of RS command is turned on and SM2591 is also turned on at the same time, if the sending length (m) is not 0, (m) bytes of the data of (s) will be sent out, and then it will enter the mode of waiting for reception. When the data is received, (N) bytes of data will be stored in (d). SM2593 will be turned ON after receiving (n) data.
374
375 In addition, when the sending length (m) is 0, it will be in the receive-only mode. When the receiving length (n) is 0, it will be in the send-only mode.
376
377 To enable the start character (STX) and the end character (ETX) modes of RS command, the status of the 10th and 11th bits of the special address SD2600 must be set. See the table below for detailed settings:
378
379 |=**Bit number**|=**Name**|=(% colspan="2" %)**Content**
380 | | |**0 (bit OFF)**|**1 (bit ON)**
381 |b0|Data length|7 digits|8 digits
382 |(((
383 b1
384
385 b2
386 )))|Parity check|(% colspan="2" %)(((
387 b2, b1
388
389 (0, 0): None
390
391 (0,1): Odd parity (ODD)
392
393 (1,1): Even parity (EVEN)
394 )))
395 |b3|Stop bit|1 bit|2 bit
396 |(((
397 b4
398
399 b5
400
401 b6
402
403 b7
404
405 b8
406
407 b9
408 )))|Baud rate (bps)|(((
409 .b9,b8,b7,b6,b5,b4
410
411 ( 0, 0, 0, 1, 1, 1): 4800
412
413 ( 0, 0, 1, 0, 0, 0): 9600
414
415 ( 0, 0, 1, 0, 0, 1): 19200
416
417 ( 0, 0, 1, 0, 1, 0): 38400
418
419 ( 0, 0, 1, 0, 1, 1): 57600
420 )))|(((
421 .b9,b8,b7,b6,b5,b4
422
423 ( 0, 0, 1, 1, 0, 0): 115200
424
425 ( 0, 0, 1, 1, 0, 1): 187500
426
427 ( 0, 0, 1, 1, 1, 0): 230400
428
429 ( 0, 0, 1, 1, 1, 1): 460800
430
431 ( 0, 1, 0, 0, 0, 0): 921600
432 )))
433 |b10|STX|Disable STX function|Enable STX function, the specific value is set by D8124
434 |b11|ETX|Disable ETX function|Enable the ETX function, the specific value is set by D8125
435 |b12|~-~-|~-~-|~-~-
436 |b13|~-~-|~-~-|~-~-
437 |b14|~-~-|~-~-|~-~-
438 |b15|~-~-|~-~-|~-~-
439
440 Example
441
442 (% style="text-align:center" %)
443 [[image:1709192957243-806.png]]
444
445 When M1 is ON, the sent and received data of communication are stored as follows after the command is executed:
446
447 [[image:1709192977624-617.png||style="float:left"]]
448
449 As shown in the figure, the sent data are 01H, 02H, 03H, 04H and 05H in turn The number of dark backgrounds used is the sent data length (m).
450
451
452 As shown in the figure, the received data are 21H, 22H, 23H and 24H in turn The number of dark backgrounds used is the received data length (n).
453
454
455
456 Some configuration and preparation of serial communication are needed for actual programming in order to achieve communication as expected. For instance, sending and receiving mode of serial port, baud rate, number of bits, parity, software protocol settings, timeout judgment conditions, and data preparation for the transceiver buffer, sending and receiving sign processing shall be set. A relatively complete RS communication setting program is shown as follows:
457
458 [[image:1709193063665-172.png||height="199" style="float:left" width="294"]]
459
460 Set the protocol to a user-defined protocol,
461
462 Sending interval: 5ms,
463
464 Reception timeout: 100ms,
465
466 Retries: 3 times,
467
468 Character interval timeout: 30ms,
469
470 Sending starting address D200 of user-defined protocol: sending length 8,
471
472 Directly trigger sending upon being.
473
474 For detailed user-defined protocol instructions, please refer to “9.5.1 User-defined Protocol Description”.
475
476
477 **Modbus protocol**
478
479 When the protocol is set to Modbus master station protocol (whether it is RTU or ASCII), When the contact in front of the RS command is set ON. RS2 command will judge whether the data of (N) is needed to send the combined data frame according to station number function code (s), slave station address (m), the length (d) and function code.
480
481 (% style="text-align:center" %)
482 [[image:1709193191809-462.png]]
483
484 After receiving, directly close the command and reset the command receiving sign.
485
486 |=**Parameter**|=**Content**
487 |(s)|The high byte stores the station number of slave station, and the low byte stores the function code of Modbus.
488 |(m)|Slave station address. The address provided by the slave station will read or write data from the address of slave station.
489 |(d)|Length: the length read or written by Modbus. The unit is determined by function code.
490 |(n)|(((
491 The starting address for data to be read or written.
492 )))
493
494 [[image:1709193250935-338.png||height="138" style="float:left" width="296"]]
495
496 Communication protocol setting:
497
498 Sending interval: 5ms
499
500 Reception timeout: 100ms
501
502 Timeout retry times: 3 times
503
504 Station number 01H, function code 03H, slave station
505
506 As shown in above ladder diagram:
507
508 When M1 is turned ON, PLC will send data (hexadecimal) from COM2 of PLC: 01 03 00 0A 00 05 A5 C8
509
510 01: represents slave address, the high 8 bits of (s);
511
512 03: Modbus command code, the low 8 bits of (s), which means to read the slave register;
513
514 00 0A: the address of slave register to be read, the value of (m);
515
516 00 05: the number of registers to be read, the value of (d),
517
518 A5 C8: CRC parity code.
519
520 For detailed user-defined protocol instructions, please refer to “9.5.2 Modbus Protocol Description”.
521
522
523 Precautions
524
525 1. Although the RS command currently allows all the parameters of the command to use constants such as K and H, different protocols have different restrictions.
526 1. When the protocol is a user-defined protocol, S and D cannot be constants, otherwise it will report (3189H) error.
527 1. When the protocol is Modbus protocol, n cannot be a constant, otherwise it will report (3189H) error.
528 1. The combination of RTU protocol and 7-bit data bits cannot be set.
529 1. If the serial port parameter settings are different, it may still be able to communicate. At present, it is normal.
530 1. Currently, the RS comand cannot be used in interrupts and events.
531
532 Error code
533
534 |=(% style="width: 113px;" %)**Error code**|=(% style="width: 897px;" %)**Content**
535 |(% style="width:113px" %)4085H|(% style="width:897px" %)(s), (m), (d) and (n) read address exceeds the range of the device.
536 |(% style="width:113px" %)3180H|(% style="width:897px" %)COM2 data reception error. There may be interference on the communication cable, it is recommended to connect GND.
537 |(% style="width:113px" %)3181H|(% style="width:897px" %)COM2 data reception timeout. Check the wiring, whether the serial port parameter settings correspond to master and slave, and whether there is interference. Check whether it is caused by the late response from the slave station. It is recommended to increase the sending interval SD2546.
538 |(% style="width:113px" %)3182H|(% style="width:897px" %)COM2 CRC parity error. There may be interference on the communication cable, it is recommended to connect GND.
539 |(% style="width:113px" %)3183H|(% style="width:897px" %)COM2 LRC parity error. There may be interference on the communication cable, it is recommended to connect GND.
540 |(% style="width:113px" %)3184H|(% style="width:897px" %)The COM2 station number is incorrectly configured. Check the slave station number setting, and check whether there is any problem with the receiving and sending mechanism from slave station.
541 |(% style="width:113px" %)3185H|(% style="width:897px" %)COM2 send buffer overflow If this error message appears, please contact technical personnel
542 |(% style="width:113px" %)3186H|(% style="width:897px" %)COM2 function code is wrong. Check whether the set function code is a function code supported by PLC.
543 |(% style="width:113px" %)3187H|(% style="width:897px" %)COM2 address is wrong. Check whether the slave station has this address. (Please refer to Modbus exception 02).
544 |(% style="width:113px" %)3188H|(% style="width:897px" %)The length of COM2 is wrong. Check whether the communication length exceeds the length range specified by Modbus protocol or user-defined protocol.
545 |(% style="width:113px" %)3189H|(% style="width:897px" %)COM2 data error. Check whether parameters of the command are wrong. Check whether the set value is supported by the slave station. (Please refer to Modbus exception 03).
546 |(% style="width:113px" %)318AH|(% style="width:897px" %)COM2 slave station is busy. Message returned from slave station: Slave station is busy. (Please refer to Modbus exception 06).
547 |(% style="width:113px" %)318BH|(% style="width:897px" %)COM2 slave station does not support function codes. Check whether this function code is supported by the slave station. (Please refer to Modbus exception 01).
548 |(% style="width:113px" %)318CH|(% style="width:897px" %)COM2 slave station is faulty. Message returned from slave station: Slave station failed, please check whether slave station failed. (Please refer to Modbus exception 04).
549 |(% style="width:113px" %)318DH|(% style="width:897px" %)COM2 slave station confirmation. Message returned from slave station: slave station confirmation. (Please refer to Modbus exception 05).
550 |(% style="width:113px" %)318EH|(% style="width:897px" %)At present, COM2 does not support this command or function. When the slave protocol is set, the communication commands related to master station or master station functions cannot be used. Please change the protocol or close the contact before the corresponding command or close the corresponding communication function.
551 |(% style="width:113px" %)318FH|(% style="width:897px" %)COM2 sending timeout. If this error message appears, please contact technical personnel.
552 |(% style="width:113px" %)31A0H|(% style="width:897px" %)No available gateway for COM2 Message returned from the slave station: no available gateway. (Please refer to Modbus exception 0A).
553 |(% style="width:113px" %)31A1H|(% style="width:897px" %)COM2 indicates that no response was obtained from the target device. Message returned from the slave station: The device is not networked. (Please refer to Modbus Exception 0B).
554
555 == **Instructions for Use of RS Instruction Protocol** ==
556
557 ----
558
559 === **User-defined Protocol Description** ===
560
561 ----
562
563 Introduction
564
565 The function of user-defined protocol: it can directly transmit data with equipment without any processing or the customer can set corresponding protocol to communicate with other equipment.
566
567 At present, the user-defined protocol of 6V PLC is configured and sent by COM2, and the command used is RS command. Protocol and serial port parameters need to be configured through devices.
568
569 The current user-defined protocol is generally similar to 3V.
570
571 Basic Configuration
572
573 (1)Instruction
574
575 The RS command itself is used in the same way as the previous RS command at 3V, and R devices can be used.
576
577 -[RS (s) (m) (d) (n)]
578
579 Content, range and data type
580
581 |=**Parameter**|=**Content**|=**Range**|=**Data type**|=**Data type (label)**|=**Custom Variable Type**
582 |(s)|The starting address of the register area where the data to be sent is stored|-|Unsigned BIN16 bits|ANY16|~-~-
583 |(m)|The length (in bytes) of the data to be sent|0~~528|Unsigned BIN16 bits|ANY16|~-~-
584 |(d)|The start number of device that stores written data|-|Unsigned BIN16 bits|ANY16|~-~-
585 |(n)|Volume of data written|0~~528|Unsigned BIN16 bits|ANY16|~-~-
586
587 Device used
588
589 |=**Instruction**|=**Parameter**|=(% colspan="24" %)**Devices**|=**Index modification**|=**Pulse expansion**
590 | | |**X**|**Y**|**M**|**S**|**SM**|**T(bit)**|**C(bit)**|**LC(bit)**|**HSC(bit)**|**D.b**|**KnX**|**KnY**|**KnM**|**KnS**|**T**|**C**|**D**|**R**|**SD**|**LC**|**HSC**|**K**|**H**|**E**|**[D]**|**XXP**
591 |(% colspan="1" rowspan="4" %)RS|Parameter 1| | | | | | | | | | | | | | |●|●|●|●| | | |●|●| | |
592 |Parameter 2| | | | | | | | | | | | | | |●|●|●|●| | | |●|●| | |
593 |Parameter 3| | | | | | | | | | | | | | |●|●|●|●| | | |●|●| | |
594 |Parameter 4| | | | | | | | | | | | | | |●|●|●|●| | | |●|●| | |
595
596 (% class="box infomessage" %)
597 (((
598 **✎**Note:
599
600 Although the RS command currently allows all the parameters of the command to use constants such as K and H, different protocols have different restrictions.
601
602 When the protocol is user-defined protocol, S and D cannot be constants, otherwise an error will be reported.
603 )))
604
605 (2)Special device setting
606
607 Special address table
608
609 |=(% colspan="2" %)**COM2 special D device (SD)**|=(% colspan="2" %)**COM2 special M device (SM)**
610 |2590|Communication port settings|2590|Sending control on
611 |2591|COM1 serial port parameter modification sign|2591|Send control/send prompt
612 |2592|Protocol settings|2592|Reception control on
613 |2593|Protocol modification sign|2593|Accept control/receive prompt
614 |2594|Station number settings|2594|8-bit mode (for user-defined protocol)
615 |2595|Station number modification sign|2595|
616 |2596|(((
617 Sending interval (0.1ms) 0~~32767
618
619 Set 0 to 10 (1ms)
620 )))|2596|
621 |2597|(((
622 Communication timeout setting (10ms) 0~~32767
623
624 Set 0 to 10 (100ms)
625 )))|2597|
626 |2598|Timeout retry times 0~~32767|2598|
627 |2599|(((
628 Character interval timeout setting (for custom protocol) (0.1ms)
629
630 0 to 32767
631
632 Set 0 to 10 (1ms)
633 )))|2599|
634 |2600|STX value|2600|
635 |2601|ETX value|2601|
636 |...| |...|
637 |2610|Volume of data received|2610|Communication completion sign
638 |2611|Last error|2611|Receiving sign
639 |2612|Current error|2612|Retry
640 |2613|Error steps|2613|Communication error
641 |2614|Error station number|2614|Communication timeout
642 |2615|Cumulative error times|2615|
643
644 The contents that will be used or set by the user-defined protocol have been marked with “underline” and “in bold”.
645
646 In addition, the devices to be used as judgment conditions have been marked “in bold” in the table.
647
648 (% class="box infomessage" %)
649 (((
650 **✎**Note:
651
652 at present, COM1 doesn’t support user-defined protocol.
653 )))
654
655 Communication port settings SD2590
656
657 |=**Bit number**|=**Name**|=(% colspan="2" %)**Content**
658 | | |**0 (bit OFF)**|**1 (bit ON)**
659 |b0|Data length|7 digits|8 digits
660 |(((
661 b1
662
663 b2
664 )))|Parity check|(% colspan="2" %)(((
665 b2, b1
666
667 (0, 0): None
668
669 (0,1): Odd parity (ODD)
670
671 (1,1): Even parity (EVEN)
672 )))
673 |b3|Stop bit|1 bit|2 bit
674 |(((
675 b4
676
677 b5
678
679 b6
680
681 b7
682
683 b8
684
685 b9
686 )))|Baud rate (bps)|(((
687 .b9,b8,b7,b6,b5,b4
688
689 ( 0, 0, 0, 1, 1, 1): 4800
690
691 ( 0, 0, 1, 0, 0, 0): 9600
692
693 ( 0, 0, 1, 0, 0, 1): 19200
694
695 ( 0, 0, 1, 0, 1, 0): 38400
696
697 ( 0, 0, 1, 0, 1, 1): 57600
698 )))|(((
699 .b9,b8,b7,b6,b5,b4
700
701 ( 0, 0, 1, 1, 0, 0): 115200
702
703 ( 0, 0, 1, 1, 0, 1): 187500
704
705 ( 0, 0, 1, 1, 1, 0): 230400
706
707 ( 0, 0, 1, 1, 1, 1): 460800
708
709 ( 0, 1, 0, 0, 0, 0): 921600
710 )))
711 |b10|STX|Disable STX function|Enable STX function, the specific value is set by D8124
712 |b11|ETX|Disable ETX function|Enable the ETX function, the specific value is set by D8125
713
714 According to the bit setting provided in the above table, the serial port parameter is set to SD2590. At present, the setting is basically the same as 3V. As a higher baud rate can be set, the bits used for enabling STX and ETX need to be moved back by two bits.
715
716 For instance, set serial port parameters: baud rate: 115200, stop bit: 1, data bit: 8, parity bit: none, enable STX.
717
718 Then set the value H4C1 (K1217) on SD2590. At present, the parameters directly set to SD2590 are only valid in the first cycle of PLC RUN, and if they need to be modified during RUN, they can be set by PORTPARAM command.
719
720
721 Protocol settings SD2592
722
723 |=(% colspan="2" %)**Protocol settings**|=(% colspan="2" %)**Protocol settings**
724 |0 H|Wecon Modbus slave station|10 H|User-defined protocol
725 |2 H|Modbus RTU slave station|20 H|Modbus RTU master station
726 |3 H|Modbus ASCII slave station|30 H|Modbus ASCII master station
727
728 The corresponding protocol can be set by setting the corresponding value in SD2592.
729
730 At present, the parameters directly set to SD2590 are only valid in the first cycle of PLC RUN.
731
732 If the parameters need to be modified during RUN, they can be set by PROTOCOL command.
733
734
735 Sending interval SD2596
736
737 The main function of sending interval is: to determine how long does it take to wait to send the next command when one command is completed. When 0 is set, it will not wait for sending at specified interval, but it will be affected by scanning period.
738
739 The unit of transmission interval is 0.1 ms, i.e. the interval time is 10ms when the value is set to be 100.
740
741
742 Communication timeout SD2597 and timeout retry SD2598
743
744
745 (% style="text-align:center" %)
746 [[image:1709194693483-466.png]]
747
748 The main function of communication timeout is: to determine when the retry is required or an error needs to be reported when the data is not received after being sent by PLC. When 0 is set, it is 100ms by default.
749
750 The unit of transmission interval is 10ms, i.e. the timeout judgment time is 100ms when the value is set to be 10.
751
752 When receiving timeout occurs, it will judge whether there are retries and the current retry times. If the retry times are greater than or equal to SD2598, an error will be reported.
753
754 If SD2598 is set to 0, no retry is required.
755
756 When it is set to 1, send the data once and then send it again after timeout.
757
758
759 Character interval timeout SD2599
760
761 At present, this setting is available for user-defined protocol.
762
763 The main function of character interval timeout is: after receiving at least one character before there is no communication timeout, judge whether the interval time between the following two characters exceed the time limit, report an error if it exceeds the time limit, and end communication.
764
765 (% style="text-align:center" %)
766 [[image:1709194729585-457.png]]
767
768 This setting is mainly designed after considering that some devices may send data slowly or there are other specific sending requirements. No retry is required in case of character interval timeout.
769
770
771 **Serial port parameter setting command**
772
773 Upper computer interface settings
774
775 (% style="text-align:center" %)
776 [[image:1709194773560-219.png]]
777
778 Through the PLC parameter setting in the upper computer interface, if the protocol is switched to “no protocol”, it means the user-defined protocol.
779
780 Serial port parameters mainly include baud rate, data bits and other serial port parameters.
781
782 Start/end characters can be sent when start characters are enabled. Start/end characters will be distinguished when they are received. See the instructions in the sending and receiving process for details.
783
784 It is important to note that the characters here are actually decimal values.
785
786 PORTPARA command
787
788 -[PORTPARA (s) (n)]
789
790 Content, range and data type
791
792 |=**Parameter**|=**Content**|=**Range**|=**Data type**|=**Data type (label)**|=**Custom variable type**
793 |(s)|Serial port parameters to be set|0 to 256|Unsigned BIN16 bits|ANY16|~-~-
794 |(n)|Which communication port to set, 0 means COM1, 1 means COM2|0, 1|Unsigned BIN16 bits|ANY16|INT
795
796 Device used
797
798 |=**Instruction**|=**Parameter**|=(% colspan="24" %)**Devices**|=**Index modification**|=**Pulse expansion**
799 | | |**X**|**Y**|**M**|**S**|**SM**|**T(bit)**|**C(bit)**|**LC(bit)**|**HSC(bit)**|**D.b**|**KnX**|**KnY**|**KnM**|**KnS**|**T**|**C**|**D**|**R**|**SD**|**LC**|**HSC**|**K**|**H**|**E**|**[D]**|**XXP**
800 |(% colspan="1" rowspan="2" %)PROTOCOL|Parameter 1| | | | | | | | | | | |●|●|●|●|●|●|●|●| | |●|●| |●|●
801 |Parameter 2| | | | | | | | | | | |●|●|●|●|●|●|●|●| | |●|●| |●|●
802
803 Function
804
805 It is used to set the communication protocol at the time of RUN, and the above command is actually used to set a specific value for the parameter modification sign.
806
807 ●The specific calculation formula is: (parameter setting value + offset of the corresponding serial port's initial special device + 10)*2
808
809 For example, setting the protocol to Modbus RTU master station (H20), i.e. (0x20 +2593-2590 +10) * 2, which is (32 +3 +10) *2=90, which mainly aims to avoid random modification of serial port parameters during operation.
810
811 For user-defined protocol, if the set parameters are triggered, the value will be changed only after the command is completely completed.
812
813 For Modbus master station protocol, if the set parameters are triggered, the value will be changed only after the command is completely completed.
814
815 For Modbus slave station protocol, if the set parameters are triggered, switching can be performed when the received data is not being processed.
816
817 For details, please refer to “PROTOCOL Instruction Description”.
818
819
820 Priority description of serial port parameters
821
822 The priority of serial port parameter setting is listed below. At present, serial port parameters are saved at the time of power failure.
823
824 Serial port parameter setting command setting = using ladder diagram MOV command to set corresponding SD device > upper computer downloading parameters > previous data saved at the time of power outage.
825
826
827 **Basic ladder diagram**
828
829 [[image:1709195811192-573.png||height="294" style="float:left" width="419"]]
830
831 Setting serial port parameters:
832
833 Baud rate: 115200, stop bit: 1, data bit: 8, parity
834
835 Set the protocol to a user-defined protocol
836
837 Sending interval: 5ms
838
839 Reception timeout: 100ms
840
841 Retries: 3 times
842
843 Character interval timeout: 30ms
844
845 Sending starting address D200 of user-defined protocol: sending length 8
846
847 Directly trigger sending upon being
848
849 After receiving, directly close the command and reset the command receiving sign.
850
851 1.Sending and receiving mechanism
852
853
854 (1)No start character (STX) and end character (ETX)
855
856 16-bit (SM2594 is OFF)
857
858 Devices will be divided into high and low directly and then the data in the low address will be sent first, followed by the data in the high address.
859
860 (% style="text-align:center" %)
861 [[image:1709197260367-911.png]]
862
863 [[image:1709197271332-974.png||height="183" style="float:left" width="161"]]
864
865 For instance, the sent data are 01, 02, 03, 04 and 05
866
867
868
869 When X1 is ON, the sent and received data of communication are stored as follows after the command is executed.
870
871 For instance, the received data are 11, 12, 13 and 14
872
873
874 8-bit (SM2594 is ON)
875
876 Get the value of the low address of the device directly and send it
877
878 (% style="text-align:center" %)
879 [[image:1709197320390-469.png]]
880
881 (% style="text-align:center" %)
882 [[image:1709197331830-332.png]]
883
884 As shown in above ladder diagram and under above data transmission, the sent data should be: 70 E1 31 62 6C.
885
886 (% style="text-align:center" %)
887 [[image:1709197349815-564.png]]
888
889 The received data will also be stored at low address.
890
891 (2)Opening and setting the start character STX
892
893 The value of the start character SD2600 is valid only when it is at low bit.
894
895 When STX is opened, the data will start with the start character STX at the time of sending, and the data starting with STX will be received, but no STX will be shown.
896
897 When the data starting with STX is received in the half way,the reception process will restart.
898
899 If the first character is not received, it will be judged as time out in case of the timeout of the first character; if the first character is received, no matter what kind of data is received, the character timeout will be counted since the last character is received.
900
901 (% style="text-align:center" %)
902 [[image:1709197411454-969.png]]
903
904
905 (% style="text-align:center" %)
906 [[image:1709197419797-167.png]]
907
908 As shown in above ladder diagram and under above data transmission, the sent data should be FE 70 7D E1 00 31.
909
910 If FE 51 26 34 15 is sent to PLC, the following data will be received.
911
912 If FE 25 63 FE 51 26 34 15 is sent to PLC, the following data will be received.
913
914 (% style="text-align:center" %)
915 [[image:1709197434533-834.png]]
916
917
918 2.Opening and setting the end character ETX
919
920 The value of the end character SD2601 is valid only when it is at low bit.
921
922 When ETX is opened, the data will end with ETX at the end of sending.
923
924 SM2610 and SM2593 are immediately ON when an ETX is received, no matter whether sufficient length of data is received.
925
926 (% style="text-align:center" %)
927 [[image:1709197515381-874.png]]
928
929 (% style="text-align:center" %)
930 [[image:1709197524487-888.png]]
931
932
933 As shown in above ladder diagram and under above data transmission, the result is 70 7D E1 00 31 FD.
934
935 As shown in above ladder diagram, if 01 06 FD is sent, the following data will be received. If FD is sent directly, it will be judged as “end” directly.
936
937 (% style="text-align:center" %)
938 [[image:1709197546086-345.png]]
939
940
941 Both start character (STX) and end character (ETX) are opened
942
943 When both start character and end character are opened, it is generally deemed as the combination of above single open state.
944
945 However, if only ETX data is received when both characters are opened, it will not end immediately, but it will change to judge the character interval time, without starting to receive data.
946
947
948 **Receiving after sending (similar to Modbus master station mechanism)**
949
950 1.** **OFF (default) state of sending control switch (SM2590) and receiving control switch (SM2592)
951
952 When the contact point of RS command is set ON, SM2591 will be sent immediately when it is set ON, and SM2591 will be automatically set OFF after sending.
953
954 After sending, judge the state of SM2593. If it is ON, it will stop in this command all the time and wait until it is set OFF and then receive data; if it is OFF, it will start receiving data.
955
956 After the first character timeout time (SD2597), if no character is received, it is judged as timeout; if retry time is set, retry it. If the communication cannot be achieved after retry, an error will be reported and SM2593 and SM2614 are set to be on.
957
958 After receiving the first character, judge whether the interval between characters exceeds the time set by SD2599, otherwise an error will be reported. (Please refer to “Character Interval Timeout” for details.)
959
960 If there are two or more commands, after SM2591 is set to be ON, RS command for setting the first ON will be sent, and then if this RS command is completed^^* 1^^and set to be ON, SM2591 will switch to the next RS command in the ladder diagram sequence^^* 2^^.
961
962 If there are two or more commands, another data will be sent when the data is half received, and the original command is continued to be executed for receiving until it is completed.
963
964 (% class="box infomessage" %)
965 (((
966 **✎**Note * 1: Completion refers to receiving data or reporting errors.
967
968 **✎**Note * 2: If there is no other RS command opened after the ladder diagram sequence, it will return to execute the first RS command opened in the ladder diagram sequence.
969 )))
970
971 2.Sending mode when the sending control switch (SM2590) is ON
972
973 When the sending control switch (SM2590) is ON, there is no need to control SM2591 to be set as ON.
974
975 At this time, as long as the contact of RS command is triggered, it can be sent, and SM2591 is automatically set as ON.
976
977 3.Receiving mode when the receiving control switch (SM2592) is ON
978
979 When the receiving control switch (SM2592) is ON, SM2593 is automatically turned to OFF when the command is executed.
980
981 When receiving, the status of SM2593 will not be judged again, and SM2593 will still be set as ON after receiving.
982
983 4.ON state of sending control switch (SM2590) and receiving control switch (SM2592)
984
985 Under above circumstance, the data can be sent only by triggering the contact in front of the RS command, which will automatically turn to the waiting for receiving state, and when the reception is completed, it will turn to the next opened RS command.
986
987
988 (3)Send only
989
990 (% style="text-align:center" %)
991 [[image:1709197775117-634.png]]
992
993 When the sending length is set to a non-0 value, the receiving length is set to 0. This is send-only mode.
994
995 1.OFF state of sending control switch (SM2590)
996
997 When SM2591 is set as ON, it sends data and does not receive data.
998
999 If there are two or more commands, after SM2591 is set to be ON, RS command for setting the first ON will be sent, and then if this RS command is completed and set to be ON, SM2591 will switch to the next RS command in the ladder diagram.
1000
1001 2.ON state of sending control switch (SM2590)
1002
1003 The data will be sent when RS command is triggered.
1004
1005 When several commands are triggered, the data will be set in circular manner, and during the circular sending, the data will be sent at intervals according to the set sending intervals.
1006
1007
1008 (4)Receive-only
1009
1010 (% style="text-align:center" %)
1011 [[image:1709197838060-527.png]]
1012
1013 When the sending length is set to a non-0 value, the receiving length is set to 0. This is send-only mode.
1014
1015 1.OFF state of sending control switch (SM2590)
1016
1017 When SM2591 is set as ON, it sends data and does not receive data.
1018
1019 If there are two or more commands, after SM2591 is set to be ON, RS command for setting the first ON will be sent, and then if this RS command is completed and set to be ON, SM2591 will switch to the next RS command in the ladder diagram.
1020
1021 2.ON state of sending control switch (SM2590)
1022
1023 The data will be sent when RS command is triggered.
1024
1025 When several commands are triggered, the data will be set in circular manner, and during the circular sending, the data will be sent at intervals according to the set sending intervals.
1026
1027 (5)Sending after receiving by the receive-only and send-only mode (similar to Modbus slave station mechanism)
1028
1029 [[image:1709715782626-666.png||height="247" style="float:left" width="233"]]
1030
1031
1032 Receive-only: when it is judged as completing reception, the command to be triggered will be judged according to the received contents; meanwhile, the received data will be saved.
1033
1034
1035
1036 Send-only: the sent contents are different after M2 is triggered and M3 is triggered. After the trigger is over, they will return to trigger the receive-only part of M1.
1037
1038
1039 A. 9.5.1.4 Error information
1040
1041 The current error code will be displayed in theSD7, SD0 and SD2611 and SD2612.
1042
1043 The error codes that will occur in user-defined protocols are mainly shown as follows:
1044
1045 |=(% style="width: 108px;" %)**Error code**|=(% style="width: 902px;" %)**Content**
1046 |(% style="width:108px" %)3181H|(% style="width:902px" %)Data reception timeout
1047 |(% style="width:108px" %)3188H|(% style="width:902px" %)Length error
1048 |(% style="width:108px" %)3189H|(% style="width:902px" %)COM2 data error. “Check whether the parameters of the command are wrong. Check whether the set value is supported by the slave station. (Please refer to Modbus exception 03).”
1049 |(% style="width:108px" %)318EH|(% style="width:902px" %)At present, COM2 does not support this command or function. When the slave protocol is set, the communication commands related to master station or master station functions cannot be used. Please change the protocol or close the contact before the corresponding command or close the corresponding communication function.
1050 |(% style="width:108px" %)318FH|(% style="width:902px" %)COM2 sending timeout. If this error message appears, please contact technical personnel.
1051 |(% style="width:108px" %)3190H|(% style="width:902px" %)COM2 receives data beyond the cache limit.
1052
1053 After resetting the protocol or communication parameters, the reported errors will be cleared.
1054
1055 In addition, in case of communication completion/communication error/communication timeout, the sign bit will be set after executing the command.
1056
1057 B.9.5.1.5 Difference with Mitsubishi
1058
1059 Currently known difference:
1060
1061 ⑴ For STX and ETX, Mitsubishi can set a maximum of 4 bytes, but we only have one byte.
1062
1063 ⑵Support accumulation, parity, CR and LF.
1064
1065 ⑶Mitsubishi's command control is to execute the command on a fixed basis when the command is triggered first. It will not be switched to other commands midway unless the contact of this command is closed.
1066
1067
1068 === **Modbus Protocol Description** ===
1069
1070 ----
1071
1072 [[image:file:///C:\Users\ADMINI~~1\AppData\Local\Temp\ksohtml10940\wps1.png]]Introduction
1073
1074 The current Modbus master station protocol is generally similar to LX3V. The address is modified in the slave station part.
1075
1076 Basic Configuration
1077
1078 (1) Instruction
1079
1080 The RS command itself is used in the same way as the previous RS command at 3V. R device can be used.
1081
1082 -[RS (s) (m) (d) (n)]
1083
1084 Content, range and data type
1085
1086 |=**Parameter**|=**Content**|=**Range**|=**Data type**|=**Data type (label)**
1087 |(s)|The high byte stores the station number of slave station, and the low byte stores the function code of Modbus.|-|Unsigned BIN16 bits|ANY16
1088 |(m)|Slave station address. The address provided by the slave station will read or write data from the address of slave station.|-|Unsigned BIN16 bits|ANY16
1089 |(d)|Length: the length read or written by Modbus. The unit is determined by function code.|-|Unsigned BIN16 bits|ANY16
1090 |(n)|The starting address for data to be read or written.|-|Unsigned BIN16 bits|ANY16
1091
1092 Device used
1093
1094 |=**Instruction**|=**Parameter**|=(% colspan="24" %)**Devices**|=**Index modification**|=**Pulse expansion**
1095 | | |**X**|**Y**|**M**|**S**|**SM**|**T(bit)**|**C(bit)**|**LC(bit)**|**HSC(bit)**|**D.b**|**KnX**|**KnY**|**KnM**|**KnS**|**T**|**C**|**D**|**R**|**SD**|**LC**|**HSC**|**K**|**H**|**E**|**[D]**|**XXP**
1096 |(% colspan="1" rowspan="4" %)RS|Parameter 1| | | | | | | | | | | | | | |●|●|●|●| | | |●|●| | |
1097 |Parameter 2| | | | | | | | | | | | | | |●|●|●|●| | | |●|●| | |
1098 |Parameter 3| | | | | | | | | | | | | | |●|●|●|●| | | |●|●| | |
1099 |Parameter 4| | | | | | | | | | | | | | |●|●|●|●| | | | | | | |
1100
1101 (% class="box infomessage" %)
1102 (((
1103 **✎Note:**
1104
1105 Although the RS command currently allows all the parameters of the command to use constants such as K and H,
1106
1107 different protocols have different restrictions. When the protocol is Modbus master station protocol, n cannot be a constant, otherwise it will report an error.
1108 )))
1109
1110 (2) Special device setting
1111
1112 Special address table
1113
1114 |=(% colspan="2" %)**COM1 special D device (SD)**
1115 |2540|Communication port settings
1116 |2541|COM1 serial port parameter modification sign
1117 |2542|
1118 |2543|
1119 |2544|Station number settings
1120 |2545|Station number modification sign
1121
1122 (% class="box infomessage" %)
1123 (((
1124 **✎Note：** COM1 doesn’t support modification of protocol.
1125 )))
1126
1127 |=(% colspan="2" style="width: 502px;" %)**COM2 special D device (SD)**|=(% colspan="2" style="width: 508px;" %)**COM2 special M device (SM)**
1128 |2590|(% style="width:440px" %)Communication port settings|(% style="width:65px" %)2590|(% style="width:443px" %)Sending control on
1129 |2591|(% style="width:440px" %)COM1 serial port parameter modification sign|(% style="width:65px" %)2591|(% style="width:443px" %)Send control/send prompt
1130 |2592|(% style="width:440px" %)Protocol settings|(% style="width:65px" %)2592|(% style="width:443px" %)Reception control on
1131 |2593|(% style="width:440px" %)Protocol modification sign|(% style="width:65px" %)2593|(% style="width:443px" %)Accept control/receive prompt
1132 |2594|(% style="width:440px" %)Station number settings|(% style="width:65px" %)2594|(% style="width:443px" %)8-bit mode (for user-defined protocol)
1133 |2595|(% style="width:440px" %)Station number modification sign|(% style="width:65px" %)2595|(% style="width:443px" %)
1134 |2596|(% style="width:440px" %)(((
1135 Sending interval (0.1ms) 0-32767
1136
1137 Set 0 to 10 (1ms)
1138 )))|(% style="width:65px" %)2596|(% style="width:443px" %)
1139 |2597|(% style="width:440px" %)(((
1140 Communication timeout setting (10ms) 0-32767
1141
1142 Set 0 to 10 (100ms)
1143 )))|(% style="width:65px" %)2597|(% style="width:443px" %)
1144 |2598|(% style="width:440px" %)Timeout retry times 0-32767|(% style="width:65px" %)2598|(% style="width:443px" %)
1145 |2599|(% style="width:440px" %)(((
1146 Character interval timeout setting (for custom protocol) (0.1ms)
1147
1148 0 to 32767
1149
1150 Set 0 to 10 (1ms)
1151 )))|(% style="width:65px" %)2599|(% style="width:443px" %)
1152 |2600|(% style="width:440px" %)STX value|(% style="width:65px" %)2600|(% style="width:443px" %)
1153 |2601|(% style="width:440px" %)ETX value|(% style="width:65px" %)2601|(% style="width:443px" %)
1154 |...|(% style="width:440px" %) |(% style="width:65px" %)..|(% style="width:443px" %)
1155 |2610|(% style="width:440px" %)Volume of data received|(% style="width:65px" %)2610|(% style="width:443px" %)Communication completion sign
1156 |2611|(% style="width:440px" %)Last error|(% style="width:65px" %)2611|(% style="width:443px" %)Receiving sign
1157 |2612|(% style="width:440px" %)Current error|(% style="width:65px" %)2612|(% style="width:443px" %)Retry
1158 |2613|(% style="width:440px" %)Error steps|(% style="width:65px" %)2613|(% style="width:443px" %)Communication error
1159 |2614|(% style="width:440px" %)Error station number|(% style="width:65px" %)2614|(% style="width:443px" %)Communication timeout
1160 |2615|(% style="width:440px" %)Cumulative error times|(% style="width:65px" %)2615|(% style="width:443px" %)
1161
1162 The contents that will be used or set by the Modbus protocol have been marked with “underline” and “in bold”.
1163
1164 In addition, the devices to be used as judgment conditions have been marked “in bold” in the table.
1165
1166 1.Communication port settings SD2590
1167
1168 |=**Bit number**|=**Name**|=(% colspan="2" %)**Content**
1169 | | |**0 (bit OFF)**|**1 (bit ON)**
1170 |b0|Data length|7 digits|8 digits
1171 |(((
1172 b1
1173
1174 b2
1175 )))|Parity check|(% colspan="2" %)(((
1176 b2, b1
1177
1178 (0, 0): None
1179
1180 (0,1): Odd parity (ODD)
1181
1182 (1,1): Even parity (EVEN)
1183 )))
1184 |b3|Stop bit|1 bit|2 bit
1185 |(((
1186 b4
1187
1188 b5
1189
1190 b6
1191
1192 b7
1193
1194 b8
1195
1196 b9
1197 )))|Baud rate (bps)|(((
1198 .b9,b8,b7,b6,b5,b4
1199
1200 ( 0, 0, 0, 1, 1, 1): 4800
1201
1202 ( 0, 0, 1, 0, 0, 0): 9600
1203
1204 ( 0, 0, 1, 0, 0, 1): 19200
1205
1206 ( 0, 0, 1, 0, 1, 0): 38400
1207
1208 ( 0, 0, 1, 0, 1, 1): 57600
1209 )))|(((
1210 .b9,b8,b7,b6,b5,b4
1211
1212 ( 0, 0, 1, 1, 0, 0): 115200
1213
1214 ( 0, 0, 1, 1, 0, 1): 187500
1215
1216 ( 0, 0, 1, 1, 1, 0): 230400
1217
1218 ( 0, 0, 1, 1, 1, 1): 460800
1219
1220 ( 0, 1, 0, 0, 0, 0): 921600
1221 )))
1222
1223 According to the bit setting provided in the above table, the serial port parameter is set to SD2590.
1224
1225 At present, the setting is basically the same as 3V. As a higher baud rate can be set, the bits used for enabling STX and ETX need to be moved back by two bits.
1226
1227 For instance, set serial port parameters: baud rate: 115200, stop bit: 1, data bit: 8, parity bit: none.
1228
1229 Then set the value HC1 (K1217) on SD2590.
1230
1231 At present, the parameters directly set to SD2590 are only valid in the first cycle of PLC RUN.
1232
1233 If the parameters need to be modified during RUN, they can be set by PORTPARAM command.
1234
1235 2.Protocol settings SD2592
1236
1237 |=(% colspan="4" %)**Protocol settings**
1238 |0H|Wecon Modbus slave station|10H|User-defined protocol
1239 |2H|Modbus RTU slave station|20H|Modbus RTU master station
1240 |3H|Modbus ASCII slave station|30H|Modbus ASCII master station
1241
1242 The corresponding protocol can be set by setting the corresponding value in SD2592.
1243
1244 At present, the parameters directly set to SD2590 are only valid in the first cycle of PLC RUN.
1245
1246 If the parameters need to be modified during RUN, they can be set by PROTOCOL command.
1247
1248 At present, COM1 cannot support the protocol other than W Modbus slave protocol.
1249
1250 3.Sending interval SD2596
1251
1252 The main function of sending interval is: to determine how long does it take to wait to send the next command when one command is completed. When 0 is set, it will not wait for sending at specified interval, but it will be affected by scanning period.
1253
1254 The unit of transmission interval is 0.1 ms, i.e. the interval time is 10ms when the value is set to be 100.
1255
1256 4.Communication timeout SD2597 and timeout retry SD2598
1257
1258 (% style="text-align:center" %)
1259 [[image:1709716850100-900.png]]
1260
1261 The main function of communication timeout is: to determine when the retry is required or an error needs to be reported when the data is not received after being sent by PLC. When 0 is set, it is 100ms by default.
1262
1263 The unit of transmission interval is 10ms, i.e. the timeout judgment time is 100ms when the value is set to be 10.
1264
1265 When receiving timeout occurs, it will judge whether there are retries and the current retry times. If the retry times are greater than or equal to SD2598, an error will be reported.
1266
1267 If SD2598 is set to 0, no retry is required.
1268
1269 When it is set to 1, send the data once and then send it again after timeout.
1270
1271 (3) Serial port parameter setting
1272
1273 1.PORTPARA command
1274
1275 -[PORTPARA (s) (n)]
1276
1277 Content, range and data type
1278
1279 |**Parameter**|**Content**|**Range**|**Data type**|**Data type (label)**|**Custom variable type**
1280 |(s)|Serial port parameters to be set　0~~256|-|Unsigned BIN16 bits|ANY16|INT
1281 |(n)|Which communication port to be set, 0 means COM1, 1 means COM2|(((
1282 -2147483648~~
1283
1284 2147483647
1285 )))|Unsigned BIN16 bits|ANY16|INT
1286
1287 Device used
1288
1289 |=**Instruction**|=**Parameter**|=(% colspan="24" %)**Devices**|=**Index modification**|=**Pulse expansion**
1290 | | |**X**|**Y**|**M**|**S**|**SM**|**T(bit)**|**C(bit)**|**LC(bit)**|**HSC(bit)**|**D.b**|**KnX**|**KnY**|**KnM**|**KnS**|**T**|**C**|**D**|**R**|**SD**|**LC**|**HSC**|**K**|**H**|**E**|**[D]**|**XXP**
1291 |(% colspan="1" rowspan="2" %)PORTPARA|Parameter 1| | | | | | | | | | | |●|●|●|●|●|●|●|●| | |●|●| |●|●
1292 |Parameter 2| | | | | | | | | | | |●|●|●|●|●|●|●|●| | |●|●| |●|●
1293
1294 Function
1295
1296 Used to set communication parameters at the time of RUN.
1297
1298 For details, please refer to “PORTPARA Instruction Description”.
1299
1300 2.PROTOCOL command
1301
1302 -[PROTOCOL (s) (n)]
1303
1304 Content, range and data type
1305
1306 |=**Parameter**|=**Content**|=**Range**|=**Data type**|=**Data type (label)**|=**Custom variable type**
1307 |(s)|Protocol number to be set|0 to 65535|Unsigned BIN16 bits|ANY16|INT
1308 |(n)|Which communication port to be set, 0 means COM1, 1 means COM2|1|Unsigned BIN16 bits|ANY16|INT
1309
1310 Device used
1311
1312 |=**Instruction**|=**Parameter**|=(% colspan="24" %)**Devices**|=**Index modification**|=**Pulse expansion**
1313 | | |**X**|**Y**|**M**|**S**|**SM**|**T(bit)**|**C(bit)**|**LC(bit)**|**HSC(bit)**|**D.b**|**KnX**|**KnY**|**KnM**|**KnS**|**T**|**C**|**D**|**R**|**SD**|**LC**|**HSC**|**K**|**H**|**E**|**[D]**|**XXP**
1314 |(% colspan="1" rowspan="2" %)PROTOCOL|Parameter 1| | | | | | | | | | | |●|●|●|●|●|●|●|●| | |●|●| |●|●
1315 |Parameter 2| | | | | | | | | | | |●|●|●|●|●|●|●|●| | |●|●| |●|●
1316
1317 Function
1318
1319 It is used to set the communication protocol at the time of RUN, and the above command is actually used to set a specific value for the parameter modification sign.
1320
1321 The specific calculation formula is: (parameter setting value + offset of the corresponding serial port's initial special device + 10)*2
1322
1323 For example, setting the protocol to Modbus RTU master station (H20), i.e. (0x20 +2593-2590 +10) * 2, which is (32 +3 +10) *2=90, which mainly aims to avoid random modification of serial port parameters during operation.
1324
1325 For Modbus master station protocol, if the set parameters are triggered, the value will be changed only after the command is completely completed.
1326
1327 For Modbus slave station protocol, if the set parameters are triggered, switching can be performed when the received data is not being processed.
1328
1329 For details, please refer to “PROTOCOL Instruction Description”.
1330
1331 3.Upper computer settings
1332
1333 The PLC parameter setting of the upper computer can set the corresponding serial port parameters.
1334
1335 (% style="text-align:center" %)
1336 [[image:1709717121639-464.png]]
1337
1338 Specific protocol station number cannot be 0
1339
1340 Station number under Modbus RTU and Modbus ASCII protocol is 0: Protocol sets the master station.
1341
1342 Station number under Modbus RTU and Modbus ASCII protocol is non-0: Protocol sets the slave station.
1343
1344 Serial port parameters are filled in according to the contents in the table.
1345
1346 Note: RTU protocol cannot set 7-bit data bits.
1347
1348 4.Priority description of serial port parameters
1349
1350 The priority of serial port parameter settings is listed below.
1351
1352 At present, serial port parameters are saved at the time of power failure.
1353
1354 Serial port parameter setting command setting = using ladder diagram MOV command to set corresponding SD device > upper computer downloading parameters > previous data saved at the time of power outage.
1355
1356 (4) Basic ladder diagram
1357
1358 [[image:1709717196041-407.png||height="190" style="float:left" width="409"]]
1359
1360 Serial port parameter setting
1361
1362 Baud rate: 115200, data bit: 8, parity bit: none, stop bit: 1
1363
1364 Communication protocol setting: ModbusRTU master station protocol
1365
1366 Sending interval: 5ms
1367
1368 Reception timeout: 100ms
1369
1370 Timeout retry times: 3 times
1371
1372 Station number 01H, function code 03H, slave station address 10, length 05
1373
1374 1.Sending and receiving process
1375
1376 Modbus master station
1377
1378 When programming, in front of each RS (Modbus mode) command, each operand unit should be assigned with a certain value according to the address of the communication operation object, operation type, operation register address, data number, sending or receiving unit. Once the execution starts, the system program will automatically calculate CRC parity, organize communication frames, and complete the operation of sending data and receiving response.
1379
1380 If Modbus-ASC protocol is used for communication (SD2592 is set to H30), the HEX-ASC format for sending and receiving data is automatically changed by PLC system program, and the method of using RS (Modbus mode) command by users is exactly the same as that of using Modbus-RTU protocol.
1381
1382 In the plc program, if multiple RS (Modbus Mode) commands are driven, when the system program is executed, the next RS command will be processed in the same way after the links of “sending, waiting for response, receiving, checking, analyzing and storing" of one RS command are completed, until all RS commands are executed and started again. Users don't need to care about the timing and process of its execution, which simplifies PLC programming design. This is the advantage of Modbus command.
1383
1384 List of Modbus Master Station Function
1385
1386 |=**Function code**|=**Function name**|=**Details**
1387 |0x01|Coil state readout|Coil state readout (several points)
1388 |0x02|Input readout|Input readout (several)
1389 |0x03|Holding register readout|Holding register readout (several points)
1390 |0x04|Input register readout|Input register readout (several points)
1391 |0x05|1 Coil written|Coil written (only one point)
1392 |0x06|1 Register written|Holding register written (only one point)
1393 |0x0F|Batch coil written|Multi-point coil written
1394 |0x10|Batch register written|Multi-point holding register written
1395
1396 [[image:file:///C:\Users\ADMINI~~1\AppData\Local\Temp\ksohtml13328\wps1.png]]For instance:
1397
1398 [[image:1709789901403-566.png||height="186" style="float:left" width="399"]] Serial port parameter setting
1399
1400 Baud rate: 115200, data bit: 8, parity bit: none, stop bit: 1
1401
1402 Communication protocol setting: ModbusRTU master station protocol
1403
1404 Sending interval: 5ms
1405
1406 Reception timeout: 100ms
1407
1408 Timeout retry times: 3 times
1409
1410 Station number 01H, function code 03H, slave station
1411
1412 As shown in above ladder diagram:
1413
1414 When M1 is turned ON, PLC will send data (hexadecimal) from COM2 of PLC: 01 03 00 0A 00 05 A5 C8
1415
1416 01: represents slave address, the high 8 bits of (s);
1417
1418 03: Modbus command code, the low 8 bits of (s), which means to read the slave register;
1419
1420 00 0A: the address of slave register to be read, the value of (m);
1421
1422 00 05: The number of registers to be read, the value of (d),
1423
1424 A5 C8: CRC parity code
1425
1426 (% class="box infomessage" %)
1427 (((
1428 **✎Notes**
1429
1430 With 1 coil written (0x05), if 1 is written, the used value is 0xFF00; if 0 is written, the used value is 0x0000.
1431
1432 With batch coil written (0x0F), pay attention to the high and low bytes switching. For example, when writing 1 length, the fourth parameter value is 1 (0x0001), which means sending 0, and only when 256 (0x0100) is written can 1 be written as the target address.
1433 )))
1434
1435 2.Modbus slave station
1436
1437 When plc is used as Modbus slave station, it supports communication operation commands such as 0x01, 0x03, 0x05, 0x06, 0x0f and 0x10 of Modbus; through these commands, the coils that can read and write PLC have variables such as M, S, T, C, X (read-only) SM, Y, LC, HSC, etc. Register variables include D, T, C, R, SD, LC and HSC.
1438
1439 When the Modbus communication host accesses (reads or rewrites) the internal variables of PLC slave, it must follow the following definition of communication command frame and variable address index method, so as to carry out normal communication operation.
1440
1441 **①**Instruction code 0x01 (01): read coil
1442
1443 |=**No.**|=**Data (byte) meaning**|=**Number of bytes**|=**Description**
1444 |1|Slave address|1 byte|Take value 1~~247, which is set by SD2544 and SD2594
1445 |2|0x01 (command code)|1 byte|Read coil
1446 |3|Start address of coil|2 bytes|High bit in the front and low bit in the rear, see the addressing of the coil
1447 |4|Coil number|2 bytes|High bit in the front and low bit in the rear (N)
1448 |5|CRC parity|2 bytes|High bit in the front and low bit in the rear
1449
1450 Response frame format: slave address + 0x01 + bytes + coil status + CRC parity
1451
1452 |=(% style="width: 58px;" %)**No.**|=(% style="width: 139px;" %)**Data (byte) meaning**|=(% style="width: 124px;" %)**Number of bytes**|=(% style="width: 690px;" %)**Description**
1453 |(% style="width:58px" %)1|(% style="width:139px" %)Slave address|(% style="width:124px" %)1 byte|(% style="width:690px" %)Take value 1~~247, which is set by SD2544 and SD2594
1454 |(% style="width:58px" %)2|(% style="width:139px" %)0x01 (command code)|(% style="width:124px" %)1 byte|(% style="width:690px" %)Read coil
1455 |(% style="width:58px" %)3|(% style="width:139px" %)Number of bytes|(% style="width:124px" %)1 byte|(% style="width:690px" %)Value: [(N+7)/8]
1456 |(% style="width:58px" %)4|(% style="width:139px" %)Coil state|(% style="width:124px" %)[(N+7)/8] bytes|(% style="width:690px" %)Every 8 coils are combined into one byte. If the last coil is less than 8 bits, the undefined part is filled with 0. The first 8 coils are in the first byte, and the coil with the smallest address is in the lowest bit. And so forth.
1457 |(% style="width:58px" %)5|(% style="width:139px" %)CRC parity|(% style="width:124px" %)2 bytes|(% style="width:690px" %)High bit in the front and low bit in the rear
1458
1459 Error response: see error response frame
1460
1461 ② Instruction code 0x03 (03): read register
1462
1463 Request frame format: slave address+ 0x03 + register start address + register number + CRC parity.
1464
1465 |=**No.**|=**Data (byte) meaning**|=**Number of bytes**|=**Description**
1466 |1|Slave address|1 byte|Take value 1~~247, which is set by SD2544 and SD2594
1467 |2|0x03 (command code)|1 byte|Read register
1468 |3|Register start address|2 bytes|High bit in the front and low bit in the rear, see the addressing of the register
1469 |4|Register number|2 bytes|High bit in the front and low bit in the rear (N)
1470 |5|CRC parity|2 bytes|High bit in the front and low bit in the rear
1471
1472 |=**No.**|=**Data (byte) meaning**|=**Number of bytes**|=**Description**
1473 |1|Slave address|1 byte|Take value 1~~247, which is set by SD2544 and SD2594
1474 |2|0x03 (command code)|1 byte|Read register
1475 |3|Number of bytes|1 byte|Value: N*2
1476 |4|Register value|N*2 bytes|Every two bytes represents a register value, with high bit in the front and low bit in the rear. Register with small address comes first
1477 |5|CRC parity|2 bytes|High bit in the front and low bit in the rear
1478
1479 Response frame format: slave address+0x03+bytes+register value +CRC parity.
1480
1481 Error response: see error response frame
1482
1483 ③ Instruction code 0x05 (05): write single coil
1484
1485 Response frame format: slave address + 0x05+ bytes + coil address + CRC parity
1486
1487 |=**No.**|=**Data (byte) meaning**|=**Number of bytes**|=**Description**
1488 |1|Slave address|1 byte|Take value 1~~247, which is set by SD2544 and SD2594
1489 |2|0x05 (command code)|1 byte|Write single coil
1490 |3|Coil address|2 bytes|High bit in the front and low bit in the rear, see the addressing of the coil
1491 |4|Coil state|2 bytes|High bit in the front and low bit in the rear. If the value is not 0, it is valid.
1492 |5|CRC parity|2 bytes|High bit in the front and low bit in the rear
1493
1494 Response frame format: slave address+0x05+coil address+ coil state+ CRC parity.
1495
1496 |=**No.**|=**Data (byte) meaning**|=**Number of bytes**|=**Description**
1497 |1|Slave address|1 byte|Take value 1~~247, which is set by SD2544 and SD2594.
1498 |2|0x05 (command code)|1 byte|Write single coil
1499 |3|Coil address|2 bytes|High bit in the front and low bit in the rear, see the addressing of the coil
1500 |4|Coil state|2 bytes|High bit in the front and low bit in the rear. If the value is not 0, it is valid.
1501 |5|CRC parity|2 bytes|High bit in the front and low bit in the rear
1502
1503 Error response: see error response frame
1504
1505 Wherein the coil state 0xFF00 means being set as ON and 0x0000 means being set as OFF.
1506
1507 ④ Instruction code 0x06 (06): write single register
1508
1509 Request frame format: slave address+ 0x06 + register address + register value + CRC parity.
1510
1511 |=**No.**|=**Data (byte) meaning**|=**Number of bytes**|=**Description**
1512 |1|Slave address|1 byte|Take value 1~~247, which is set by SD2544 and SD2594
1513 |2|0x06 (command code)|1 byte|Write single register
1514 |3|Register address|2 bytes|High bit in the front and low bit in the rear, see the addressing of the register
1515 |4|Register value|2 bytes|High bit in the front and low bit in the rear. If the value is not 0, it is valid.
1516 |5|CRC parity|2 bytes|High bit in the front and low bit in the rear
1517
1518 Response frame format: slave address+0x06+register address+ register value+ CRC parity.
1519
1520 |=**No.**|=**Data (byte) meaning**|=**Number of bytes**|=**Description**
1521 |1|Slave address|1 byte|Take value 1~~247, which is set by SD2544 and SD2594
1522 |2|0x06 (command code)|1 byte|Write single register
1523 |3|Register address|2 bytes|High bit in the front and low bit in the rear, see the addressing of the register
1524 |4|Register value|2 bytes|High bit in the front and low bit in the rear. If the value is not 0, it is valid.
1525 |5|CRC parity|2 bytes|High bit in the front and low bit in the rear
1526
1527 Error response: see error response frame.
1528
1529 ⑤ Instruction code 0x0f (15): write multiple coils
1530
1531 Request frame format: slave address + 0x 0f+ coil start address + coil number+ number of bytes+ coil state+ CRC parity.
1532
1533 |=**No.**|=**Data (byte) meaning**|=**Number of bytes**|=**Description**
1534 |1|Slave address|1 byte|Take value 1~~247, which is set by SD2544 and SD2594
1535 |2|0x 0f (command code)|1 byte|Write multiple coils
1536 |3|Start address of coil|2 bytes|High bit in the front and low bit in the rear, see the addressing of the coil
1537 |4|Coil number|2 bytes|High bit in the front and low bit in the rear. N, maximum value: 1968
1538 |5|Number of bytes|1 byte|Value: [(N+7)/8]
1539 |6|Coil state|[(N+7)/8] bytes|Every 8 coils are combined into one byte. If the last coil is less than 8 bits, the undefined part is filled with 0. The first 8 coils are in the first byte, and the coil with the smallest address is in the lowest bit. And so forth.
1540 |7|CRC parity|2 bytes|High bit in the front and low bit in the rear
1541
1542 Response frame format: slave address+ 0x 0f +coil start address+ coil number+ CRC parity
1543
1544 |=**No.**|=**Data (byte) meaning**|=**Number of bytes**|=**Description**
1545 |1|Slave address|1 byte|Take value 1~~247, which is set by SD2544 and SD2594
1546 |2|0x 0f (command code)|1 byte|Write multiple coils
1547 |3|Start address of coil|2 bytes|High bit in the front and low bit in the rear, see the addressing of the coil
1548 |4|Coil number|2 bytes|High bit in the front and low bit in the rear.
1549 |5|CRC parity|2 bytes|High bit in the front and low bit in the rear
1550
1551 Error response: see error response frame
1552
1553 ⑥ Instruction code 0x10 (16): write multiple registers
1554
1555 Request frame format: slave address+ 0x10 + register start address + register number +number of bytes+ register value+ CRC parity.
1556
1557 |=**No.**|=**Data (byte) meaning**|=**Number of bytes**|=**Description**
1558 |1|Slave address|1 byte|Take value 1~~247, which is set by SD2544 and SD2594
1559 |2|0x10 (command code)|1 byte|Write multiple registers
1560 |3|Register start address|2 bytes|High bit in the front and low bit in the rear, see the addressing of the register
1561 |4|Register number|2 bytes|High bit in the front and low bit in the rear. N, maximum value: 120
1562 |5|Number of bytes|1 byte|Value: N*2
1563 |6|Register value|N*2 (N*4)|
1564 |7|CRC parity|2 bytes|High bit in the front and low bit in the rear
1565
1566 Response frame format: slave address+0x10+ register start address+ register number + CRC parity.
1567
1568 |=**No.**|=**Data (byte) meaning**|=**Number of bytes**|=**Description**
1569 |1|Slave address|1 byte|Take value 1~~247, which is set by SD2544 and SD2594
1570 |2|0x10 (command code)|1 byte|Write multiple registers
1571 |3|Register start address|2 bytes|High bit in the front and low bit in the rear, see the addressing of the register
1572 |4|Register number|2 bytes|High bit in the front and low bit in the rear. N, maximum value: 120
1573 |5|CRC parity|2 bytes|High bit in the front and low bit in the rear
1574
1575 Error response: see error response frame
1576
1577 ⑦ Error response frame
1578
1579 Error response: slave address + (command code + 0x80) + error code + CRC parity.
1580
1581 |=**No.**|=**Data (byte) meaning**|=**Number of bytes**|=**Description**
1582 |1|Slave address|1 byte|Take value 1~~247, which is set by SD2544 and SD2594
1583 |2|Instruction code+0x80|1 byte|Error command code
1584 |3|Error code|1 byte|1 to 4
1585 |4|CRC parity|2 bytes|High bit in the front and low bit in the rear
1586
1587 |=(% style="width: 88px;" %)**No.**|=(% style="width: 276px;" %)**Error code**|=**Description**
1588 |(% style="width:88px" %)1|(% style="width:276px" %)01|Not supported function codes
1589 |(% style="width:88px" %)2|(% style="width:276px" %)02|Wrong address or function code
1590 |(% style="width:88px" %)3|(% style="width:276px" %)03|Wrong length
1591 |(% style="width:88px" %)4|(% style="width:276px" %)04|Incomplete command
1592 |(% style="width:88px" %)5|(% style="width:276px" %)05|Address not allowed
1593
1594 **⑧Slave station address table**
1595
1596 |=(% colspan="5" %)**Word address**
1597 |**Address type**|**Occupation**|**Address range**|**Decimal address**|**Total reserved address size**
1598 |T0 to T511|512 WORD|0x0000 to 0x01ff|0|1536
1599 |C0~~C255|256 WORD|0x0600 to 0x06ff|1536|1024
1600 |LC0 to LC255|512 WORD|0x0A000 to 0x0BFF|2560|1024
1601 |HSC0 to HSC15|128 WORD|0x0E00 to 0x0E1F|3584|512
1602 |D0~~D7999|8000 WORD|0x1000 to 0x2F3F|4096|16384
1603 |SD0 to SD4095|4096 WORD|0x5000 to 0x5FFF|20480|12288
1604 |R0~~R30000|30000 WORD|0x8000 to 0xF52F|32768|30000
1605
1606 |=(% colspan="5" %)**Bit address**
1607 |**Address type**|**Occupation**|**Address range**|**Decimal address**|**Total reserved address size**
1608 |T0 to T511|512 bit|0x0000 to 0x01ff|0|1536
1609 |C0~~C255|256 bit-|0x0600 to 0x06ff|1536|1024
1610 |LC0 to LC255|256 bit-|0x0A00 to 0x0AFF|2560|1024
1611 |HSC0 to HSC15|64 bit|0x0E00 to 0x0E0F|3584|512
1612 |M0 to M8000|8192 bit|0x1000 to 0x2F3F|4096|16384
1613 |SM0~~SM4095|4096 bit|0x5000 to 0x5FFF|20480|12288
1614 |Reserved| |0x8000 to 0xBFFF| |16383
1615 |S0 to S4095|4096 bit|0xC000 to 0xCFFF|49152|8192
1616 |X0 to X1777|1024 bit-|0xE000 to 0xE3FF|57344|4096
1617 |Y0~~Y1777|1024 bit-|0xF000 to 0xF3FF|61440|4096
1618
1619 Error information
1620
1621 The current error code will be displayed in the SD7, SD0, SD2611 and SD2612.
1622
1623 The error codes that will occur in Modbus protocols are mainly shown as follows:
1624
1625 |=**Error code**|=**Content**
1626 |4085H|(s), (m), (d) and (n) read address exceeds the range of the device （this error is displayed in SD7 and SD0 only).
1627 |3180H|COM2 data reception error. There may be interference on the communication cable, it is recommended to connect GND.
1628 |3181H|COM2 data reception timeout. Check the wiring, whether the serial port parameter settings correspond to master and slave, and whether there is interference. Check whether it is caused by the late response from slave station. It is recommended to increase the sending interval SD2546.
1629 |3182H|COM2 CRC parity error. There may be interference on the communication cable, it is recommended to connect GND.
1630 |3183H|COM2 LRC parity error. There may be interference on the communication cable, it is recommended to connect GND.
1631 |3184H|The COM2 station number is incorrectly configured. Check the slave station number setting, and check whether there is any problem with the receiving and sending mechanism from slave station.
1632 |3185H|COM2 send buffer overflow If this error message appears, please contact technical personnel.
1633 |3186H|COM2 function code is wrong. Check whether the set function code is a function code supported by PLC.
1634 |3187H|COM2 address is wrong. Check whether the slave station has this address. (Please refer to Modbus exception 02).
1635 |3188H|The length of COM2 is wrong. Check whether the communication length exceeds the length range specified by Modbus protocol or user-defined protocol.
1636 |3189H|(((
1637 COM2 data error. Check whether parameters of the command are wrong. Check whether the set value is supported by the slave station.
1638
1639 (Please refer to Modbus exception 03).
1640 )))
1641 |318AH|COM2 slave station is busy. Message returned from slave station: Slave station is busy. (Please refer to Modbus exception 06).
1642 |318BH|COM2 slave station does not support function codes. Check whether this function code is supported by the slave station. (Please refer to Modbus exception 01).
1643 |318CH|COM2 slave station is faulty. Message returned from slave station: Slave station failed, please check whether slave station failed. (Please refer to Modbus exception 04).
1644 |318DH|COM2 slave station confirmation. Message returned from slave station: slave station confirmation. (Please refer to Modbus exception 05).
1645 |318EH|At present, COM2 does not support this command or function. When the slave protocol is set, the communication commands related to master station or master station functions cannot be used. Please change the protocol or close the contact before the corresponding command or close the corresponding communication function.
1646 |318FH|COM2 sending timeout. If this error message appears, please contact technical personnel.
1647 |3190H|COM2 receives data beyond the cache limit.
1648 |31A0H|No available gateway for COM2 Message returned from the slave station: no available gateway. (Please refer to Modbus exception 0A).
1649 |31A1H|COM2 indicates that no response was obtained from the target device. Message returned from the slave station: The device is not networked. (Please refer to Modbus Exception 0B).
1650
1651 After resetting the protocol or communication parameters, the reported errors will be cleared.
1652
1653 In addition, in case of communication completion/communication error/communication timeout, the sign bit will be set after executing the command.
1654
1655
1656 == **WECON Modbus Protocol Description** ==
1657
1658 ----
1659
1660 At present, WECON Modbus protocol description (special protocol) is modified based on Modbus RTU protocol.
1661
1662 Therefore, 7-bit data bits cannot be used in serial port parameters.
1663
1664 This protocol is fully compatible with Modbus RTU protocol, and the address is the same as the default address of Modbus RTU protocol of LX6V PLC.
1665
1666 The extended function is mainly used to communicate with PLC Editor 2.
1667
1668 == [[image:file:///C:\Users\Administrator\AppData\Local\Temp\ksohtml2512\wps2.png]][[image:file:///C:\Users\Administrator\AppData\Local\Temp\ksohtml2512\wps3.png]]**10.7 Communication function block** ==
1669
1670 === [[image:file:///C:\Users\Administrator\AppData\Local\Temp\ksohtml2512\wps4.png]]**1. SERIAL_MODBUS_WR** ===
1671
1672 SERIAL_MODBUS_WR - Modbus master serial communication
1673
1674 [[image:file:///C:\Users\Administrator\AppData\Local\Temp\ksohtml2512\wps5.jpg]]
1675
1676 This function block is the setting function block for sending protocol frames by the Modbus master station (whether RTU or ASCII). When the contact in front of Enable is turned ON, according to the communication port, station number, function code, slave station address, quantity and mapped data address set by the function block, the data frame is combined and sent.
1677
1678 **Device used**
1679
1680 |(% rowspan="2" %)**Instruction**|(% rowspan="2" %)**Parameter**|(% colspan="24" %)**Device**|(((
1681 **Offset**
1682
1683 **Modification**
1684 )))|(((
1685 **Pulse**
1686
1687 **Expansion**
1688 )))
1689 |**X**|**Y**|**M**|**S**|**SM**|**T(bit)**|**C(bit)**|**LC(bit)**|**HSC(bit)**|**D.b**|**KnX**|**KnY**|**KnM**|**KnS**|**T**|**C**|**D**|**R**|**SD**|**LC**|**HSC**|**K**|**H**|**E**|**[D]**|**XXP**
1690 |(% rowspan="15" %)(((
1691 SERIAL
1692
1693 MODBUS_WR
1694 )))|Enable|●|●|●|●|●| | | | | | | | | | | | |●|●| | | | | | |
1695 |CommunicationPort| | | | | | | | | | | | |●|●|●|●|●| | | | | | | | |
1696 |SlaveID| | | | | | | | | | | | |●|●|●|●|●| | | | | | | | |
1697 |FunctionCode| | | | | | | | | | | | |●|●|●|●|●| | | | | | | | |
1698 |SlaveAddress| | | | | | | | | | | | |●|●|●|●|●| | | | | | | | |
1699 |Count| | | | | | | | | | | | |●|●|●|●|●| | | | | | | | |
1700 |Data| | | | | | | | | | | | | | |●|●| | | | | | | | | |
1701 |Done| |●|●|●|●| | | | | | | | | | | | | |●| | | | | | |
1702 |Busy| |●|●|●|●| | | | | | | | | | | | | |●| | | | | | |
1703 |InVelocity| |●|●|●|●| | | | | | | | | | | | | |●| | | | | | |
1704 |Busy| |●|●|●|●| | | | | | | | | | | | | |●| | | | | | |
1705 |Active| | | | | | | | | | | | | | |●|●| | | | | | | | | |
1706 |CommandAborted|●|●|●|●|●| | | | | | | | | | | | |●|●| | | | | | |
1707 |Error| | | | | | | | | | | | |●|●|●|●|●| | | | | | | | |
1708 |ErrorID| | | | | | | | | | | | |●|●|●|●|●| | | | | | | | |
1709
1710 **Variable Type Used**
1711
1712 |**Instruction**|(((
1713 **Pin**
1714
1715 **Type**
1716 )))|**Parameter**|(((
1717 **Variable**
1718
1719 **Type**
1720 )))|(((
1721 **Can you**
1722
1723 **Is empty**
1724 )))|**Range**|**Description**
1725 |(% rowspan="12" %)(((
1726 SERIAL
1727
1728 MODBUS_WR
1729 )))|(% rowspan="7" %)Input|Enable|BOOL|No|TRUE/FALSE|Enable sending Modbus master serial communication data
1730 |CommunicationPort|UINT|No|[0,1]|(((
1731 Communication port
1732
1733 0: Serial port 1
1734
1735 1: Serial port 2
1736 )))
1737 |SlaveID|UINT|No|[0,255]|Station number of slave station
1738 |FunctionCode|UINT|No|1/2/3/4/5/6/15/16|Function code
1739 |SlaveAddress|UINT|No|[0,65535]|The slave address ( the address provided by the slave station) will read or write data from this address of the slave station.
1740 |Count|UINT|No|-|(((
1741 Number
1742
1743 The number of Modbus reads or writes, and the unit is determined by the function code.
1744 )))
1745 |Data|ANY|No|-|The starting address for reading or writing data
1746 |(% rowspan="5" %)Output|Done|BOOL|Yes|TRUE/FALSE|Instruction completed
1747 |Busy|BOOL|Yes|TRUE/FALSE|Serial port busy
1748 |Active|BOOL|Yes|TRUE/FALSE|Instruction working
1749 |Error|BOOL|Yes|TRUE/FALSE|Error
1750 |ErrorID|DWORD|Yes|Refer to ErrorID for details|Error code
1751
1752 **Function**
1753
1754 ​Enable the MB_SERIAL function block to send the specified Modbus master serial communication data for reading from or writing to a slave station.
1755
1756 **Notice**
1757
1758 (1) If and only if the function block Enable is enabled, update the current serial communication instruction sending status;
1759
1760 (2) If two or more serial port instructions use the same serial port in the scanning program, the corresponding serial port instructions will wait for the execution of the previous serial port instruction to be completed according to the instruction order, and then execute their own communication instructions;
1761
1762 (3) If two or more serial port instructions use different serial ports in the scanning program, the corresponding serial port instructions will be executed in sequence according to the instruction order without affecting each other;
1763
1764 (4) Busy means that the serial port is busing and Active means that the current instruction is being executed.
1765
1766 **Modbus protocol**
1767
1768 When the protocol is set to Modbus master protocol (whether RTU or ASCII). When the contact in front of the MB_SERIAL function block is ON, the MB_SERIAL function block will send a combined data frame at the designated communication port according to the station number, function code, slave station address, quantity, and data starting address.
1769
1770 **Error code**
1771
1772 |**Error code**|**Content**
1773 |4084H|CommunicationPort input error (0: Serial port 1, 1: Serial port 2).
1774 |408FH|The firmware does not support this instruction, and needs to be upgraded.
1775 |4096H|The settings of Count and Data are outside the range of variables.
1776 |3180H|COM2 reception error There may be interference on the communication cable, it is recommended to connect GND.
1777 |3181H|COM2 data reception timeout. Check the wiring, whether the serial port parameter settings correspond to master and slave, and whether there is interference. Check whether it is caused by the late response from the slave station. It is recommended to increase the sending interval SD2546.
1778 |3182H|COM2 CRC parity error. There may be interference on the communication cable, it is recommended to connect GND.
1779 |3183H|COM2 LRC parity error. There may be interference on the communication cable, it is recommended to connect GND.
1780 |3184H|The COM2 station number is configuration error Check the slave station number setting, and check whether there is any problem with the receiving and sending mechanism from slave station.
1781 |3185H|COM2 send buffer overflow If this error message appears, please contact technical personnel.
1782 |3186H|COM2 function code is error. Check whether the set function code is a function code supported by PLC.
1783 |3187H|COM2 address error. Check whether the slave station has this address. (Please refer to Modbus exception 02)
1784 |3188H|The length of COM2 is wrong. Check whether the communication length exceeds the length range specified by Modbus protocol or user-defined protocol.
1785 |3189H|COM2 data error. Check whether parameters of the command are wrong. Check whether the set value is supported by the slave station. (Please refer to Modbus exception 03).
1786 |318AH|COM2 slave station is busy. Slave station return information: Slave station is busy (Please refer to Modbus exception 06).
1787 |318BH|COM2 slave station does not support function codes. Check whether this function code is supported by the slave station. (Please refer to Modbus exception 01)
1788 |318CH|COM2 slave failure. Slave station return information: Slave station failure, please check whether the slave station fails. (Please refer to Modbus exception 04)
1789 |318DH|COM2 slave station confirmation. Slave station return information: Slave confirmation (Please refer to Modbus exception 05)
1790 |318EH|At present, COM2 does not support this command or function. When the slave protocol is set, the communication commands related to master station or master station functions cannot be used. Please change the protocol or close the contact in front of the corresponding command or close the corresponding communication function.
1791 |318FH|COM2 sending timeout. If this error message appears, please contact technical personnel.
1792 |31A0H|No available gateway for COM2 Slave station return information: Unavailable gateway (Please refer to Modbus exception 0A)
1793 |31A1H|COM2 indicates that no response was obtained from the target device. Slave station return information: The device is not in the network. (Please refer to Modbus exception 0B)
1794
1795
1796 **Example**
1797
1798 **Application example**
1799
1800 Set the COM2 communication parameters through the SD device.
1801
1802 [[image:file:///C:\Users\Administrator\AppData\Local\Temp\ksohtml2512\wps6.jpg]]
1803
1804 Enable the function block and its Enable pin, send Modbus serial port master data and wait for the slave respond. Done indicates that the current instruction has been executed, Busy indicates that the serial port is busy, and Active indicates that the current instruction is running (waiting for data to be returned from the slave station).
1805
1806 [[image:file:///C:\Users\Administrator\AppData\Local\Temp\ksohtml2512\wps7.jpg]]
1807
1808
1809 1. **SERIAL_WR**
1810
1811 [[image:file:///C:\Users\Administrator\AppData\Local\Temp\ksohtml2512\wps8.png]]SERIAL_WR - Custom protocol serial communication
1812
1813 [[image:file:///C:\Users\Administrator\AppData\Local\Temp\ksohtml2512\wps9.jpg]]
1814
1815 This function block is a setting function block for user defined protocol serial port to send protocol frames. When the contact in front of Enable is turned ON. According to the communication port, sending data mapping address, sending data length, receiving data mapping address, and receiving data length set by the function block, the data frame is sent and waits for the data of the specified length to be returned.
1816
1817 **Device used**
1818
1819 |(% rowspan="2" %)**Instruction**|(% rowspan="2" %)**Parameter**|(% colspan="22" %)**Device**|(((
1820 **Offset**
1821
1822 **Modification**
1823 )))|(((
1824 **Pulse**
1825
1826 **Expansion**
1827 )))
1828 |**X**|**Y**|**M**|**S**|**SM**|**T(bit)**|**HSC(bit)**|**D.b**|**KnX**|**KnY**|**KnM**|**KnS**|**T**|**C**|**D**|**R**|**SD**|**LC**|**HSC**|**K**|**H**|**E**|**[D]**|**XXP**
1829 |(% rowspan="11" %)SERIAL_WR|Enable|●|●|●|●|●| | | | | | | | | | | | | | | | | | |
1830 |CommunicationPort| | | | | | | | | | | | |●|●|●|●|●| | | | | | |
1831 |SendData| | | | | | | | | | | | | | |●|●| | | | | | | |
1832 |SendDataLength| | | | | | | | | | | | |●|●|●|●|●| | | | | | |
1833 |ReceiveData| | | | | | | | | | | | | | |●|●| | | | | | | |
1834 |ReceiveDataLength| | | | | | | | | | | | |●|●|●|●|●| | | | | | |
1835 |Done| |●|●|●|●| | | | | | | | | | | | | | | | | | |
1836 |Busy| |●|●|●|●| | | | | | | | | | | | | | | | | | |
1837 |Active| |●|●|●|●| | | | | | | | | | | | | | | | | | |
1838 |Error| |●|●|●|●| | | | | | | | | | | | | | | | | | |
1839 |ErrorID| | | | | | | | | | | | | | |●|●| | | | | | | |
1840
1841 **Variable Type Used**
1842
1843 |**Instruction**|**Pin Type**|**Parameter**|**Variable Type**|**Can it be empty**|**Range**|**Description**
1844 |(% rowspan="11" %)SERIAL_WR|(% rowspan="6" %)Input|Enable|BOOL|No|TRUE/FALSE|Enable sending protocol-less serial communication data
1845 |CommunicationPort|UINT|No|[0,1]|Communication port, 0: Serial port 1, 1: Serial port 2
1846 |SendData|ANY|No|-|Starting address for sending data
1847 |SendDataLength|UINT|No|[0,523]|Send data length, in bytes
1848 |ReceiveData|ANY|No|-|Starting address for receiving data
1849 |ReceiveDataLength|UINT|No|[0,523]|Length of received data, in bytes
1850 |(% rowspan="5" %)Output|Done|BOOL|Yes|TRUE/FALSE|Instruction completed
1851 |Busy|BOOL|Yes|TRUE/FALSE|Serial port busy
1852 |Active|BOOL|Yes|TRUE/FALSE|Instruction working
1853 |Error|BOOL|Yes|TRUE/FALSE|Error
1854 |ErrorID|DWORD|Yes|Refer to ErrorID for details|Error code
1855
1856 **Function**
1857
1858 * Enable the PROTOCOLLESS_SERIAL function block, which can send the serial communication data of the specified custom protocol master station and wait for the data return of the slave station.
1859
1860 **Notice**
1861
1862 * If and only if the function block Enable is enabled, updating the current serial communication instruction sending state;
1863 * If two or more serial communication instructions are used simultaneously in the scanning program, the corresponding communication instructions are sequentially executed according to the instruction sequence;
1864 * Busy indicates that the serial port is busy, and Active indicates that the current instruction is being executed.
1865
1866 **User-defined protocol**
1867
1868 When the protocol is set to a custom protocol. When the contact in front of the PROTOCOLLESS_SERIAL function block is ON，The PROTOCOLLESS_ SERIAL function block will send the data starting address and sending data length in the specified communication port to send the combined data frame, and wait for the data of the received data length to be filled in the received data starting address.
1869
1870 * When the length of the transmitted data is set to 0, the mapping address of the transmitted data may not be filled in. At this time, the PROTOCOLLESS_SERIAL function block only receives data;
1871 * When the received data length is set to 0, the received data mapping address may not be filled in. At this time, the PROTOCOLLESS_SERIAL function block only sends data.
1872
1873 **Error code**
1874
1875 |**Error code**|**Content**
1876 |4084H|CommunicationPort input error (0: Serial port 1, 1: Serial port 2).
1877 |5:|The setting of SendDataLength and SendData or ReceiveDataLength and ReceiveData is outside the scope of the variable.
1878 |3181H|Data reception timeout
1879 |318EH|(((
1880 At present, COM2 does not support this command or function.
1881
1882 When set to the slave protocol, the communication instructions related to the master station or the master station function cannot be used.
1883
1884 Please change the protocol or close the contact in front of the corresponding command or close the corresponding communication function.
1885 )))
1886 |318FH|(((
1887 COM2 data reception timeout.
1888
1889 * Check wiring;
1890 * Check whether the serial port parameter settings are master-slave corresponding;
1891 * Check whether there is any interference;
1892 * Check whether it is caused by the late response from the slave station.
1893
1894 It is recommended to increase the sending interval SD2546.
1895 )))
1896 |3190H|COM2 receives data beyond the cache limit.
1897
1898
1899 **Example**
1900
1901 **Application example**
1902
1903 * Set the COM2 communication parameters through the SD device.
1904
1905 [[image:file:///C:\Users\Administrator\AppData\Local\Temp\ksohtml2512\wps10.jpg]]
1906
1907 Enables the function block and the Enable pin of the function block, sends custom protocol data and waits for the slave to respond. Done indicates that the current instruction has been executed, Busy indicates that the serial port is busy, and Active indicates that the current instruction is running (waiting for data to be returned from the slave station).