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Changes for page 08 Communication

Last modified by Iris on 2025/07/24 15:23
From version 13.1
edited by Mora Zhou
on 2025/04/29 14:19
Change comment: There is no comment for this version
To version 9.1
edited by Stone Wu
on 2022/08/30 09:58
Change comment: There is no comment for this version

Summary

Details

Page properties
Author
... ... @@ -1,1 +1,1 @@
1 -XWiki.Mora
1 +XWiki.Stone
Content
... ... @@ -2,12 +2,12 @@
2 2  
3 3  = **Modbus communication** =
4 4  
5 -== Hardware wiring ==
5 +== **Hardware wiring** ==
6 6  
7 7  The position of RS485 communication port (take VD2B as an example) is as the figure below.
8 8  
9 9  (% style="text-align:center" %)
10 -[[image:image-20220608154248-1.png||class="img-thumbnail"]]
10 +[[image:image-20220608154248-1.png]]
11 11  
12 12  Figure 8-1 The position of RS485 communication port of VD2B drive
13 13  
... ... @@ -16,7 +16,7 @@
16 16  The servo drive adopts RS485 half-duplex communication mode. The 485 bus should adopt the hand-in-hand structure instead of the star structure or the bifurcated structure. The star structure or bifurcation structure will produce reflected signals, which will affect the 485 communication.
17 17  
18 18  (% class="table-bordered" %)
19 -(% class="warning" %)|(% style="text-align:center; vertical-align:middle" %)[[image:image-20220611153134-1.png]]
19 +|(% style="text-align:center; vertical-align:middle" %)[[image:image-20220611153134-1.png]]
20 20  |(((
21 21  ✎The wiring must use shielded twisted pair, stay away from strong electricity, do not run in parallel with the power line, let alone bundle it together!
22 22  
... ... @@ -24,7 +24,7 @@
24 24  )))
25 25  
26 26  (% style="text-align:center" %)
27 -[[image:image-20220608174415-1.png||class="img-thumbnail"]]
27 +[[image:image-20220608174415-1.png]]
28 28  
29 29  Figure 8-2 RS485 communication network wiring diagram
30 30  
... ... @@ -33,7 +33,7 @@
33 33  No point in the RS485 network can be directly grounded. All devices in the network must be well grounded through their own grounding terminals.
34 34  
35 35  (% class="table-bordered" %)
36 -(% class="warning" %)|(% style="text-align:center; vertical-align:middle" %)[[image:image-20220611153144-2.png]]
36 +|(% style="text-align:center; vertical-align:middle" %)[[image:image-20220611153144-2.png]]
37 37  |Under no circumstances can the grounding wire form a closed loop.
38 38  
39 39  When wiring, consider the drive capability of the computer/PLC and the distance between the computer/PLC and the servo drive. If the drive capacity is insufficient, a repeater is needed.
... ... @@ -40,7 +40,7 @@
40 40  
41 41  = **Modbus communication protocol analysis** =
42 42  
43 -== Modbus data frame format ==
43 +== **Modbus data frame format** ==
44 44  
45 45  The VD2 series servo drives currently support the RTU communication format. The typical data frame format is shown in the table.
46 46  
... ... @@ -48,7 +48,7 @@
48 48  |=(% rowspan="2" scope="row" style="text-align: center; vertical-align: middle; width: 425px;" %)**There should be a message interval not less than 3.5 characters at the beginning**|=(% style="text-align: center; vertical-align: middle; width: 166px;" %)**Address**|=(% style="text-align: center; vertical-align: middle; width: 189px;" %)**Function code**|=(% style="text-align: center; vertical-align: middle; width: 155px;" %)**Data**|=(% style="text-align: center; vertical-align: middle; width: 158px;" %)**CRC check code**
49 49  |(% style="text-align:center; vertical-align:middle; width:166px" %)1 byte|(% style="text-align:center; vertical-align:middle; width:189px" %)1 byte|(% style="text-align:center; vertical-align:middle; width:155px" %)N bytes|(% style="text-align:center; vertical-align:middle; width:158px" %)2 bytes
50 50  
51 -== Supported function codes ==
51 +== **Description of supported function codes** ==
52 52  
53 53  The host reads and writes data to the servo through Modbus RTU format (03, 06 function codes). The corresponding Modbus function codes are as follows:
54 54  
... ... @@ -62,15 +62,15 @@
62 62  
63 63  Request format:
64 64  
65 -|=(% rowspan="2" %)**Address**|=(% rowspan="2" %)**Function code**|=(% colspan="2" %)**Initial address**|=(% colspan="2" %)**Number of reads**|=(% rowspan="2" %)**CRC check code**
66 -|=**high byte**|=**low byte**|=**high byte**|=**low byte**
65 +|(% rowspan="2" %)**Address**|(% rowspan="2" %)**Function code**|(% colspan="2" %)**Initial address**|(% colspan="2" %)**Number of reads**|(% rowspan="2" %)**CRC check code**
66 +|**high byte**|**low byte**|**high byte**|**low byte**
67 67  |1 byte|03|1 byte|1 byte|1 byte|1 byte|2 bytes
68 68  
69 69  Correct response format:
70 70  
71 71  (% style="width:1055px" %)
72 -|=(% rowspan="2" %)**Address**|=(% rowspan="2" %)**Function code**|=(% rowspan="2" style="width: 279px;" %)**Number of bytes of returned data**|=(% colspan="2" style="width: 274px;" %)**Register 1**|=(% rowspan="2" style="width: 98px;" %)**…**|=(% rowspan="2" %)**CRC check code**
73 -|=(% style="width: 160px;" %)**high byte**|=(% style="width: 114px;" %)**low byte**
72 +|(% rowspan="2" %)**Address**|(% rowspan="2" %)**Function code**|(% rowspan="2" style="width:279px" %)**Number of bytes of returned data**|(% colspan="2" style="width:274px" %)**Register 1**|(% rowspan="2" style="width:98px" %)**…**|(% rowspan="2" %)**CRC check code**
73 +|(% style="width:160px" %)**high byte**|(% style="width:114px" %)**low byte**
74 74  |1 byte|03|(% style="width:279px" %)1 byte|(% style="width:160px" %)1 byte|(% style="width:114px" %)1 byte|(% style="width:98px" %)…|2 bytes
75 75  
76 76  **Write function code: 0x06**
... ... @@ -85,16 +85,16 @@
85 85  
86 86  Response format:
87 87  
88 -|=(% rowspan="2" %)**Address**|=(% rowspan="2" %)**Function code**|=(% colspan="2" %)**Register address**|=(% colspan="2" %)**Data**|=(% rowspan="2" %)**CRC check code**
89 -|=**high byte**|=**low byte**|=**high byte**|=**low byte**
88 +|(% rowspan="2" %)**Address**|(% rowspan="2" %)**Function code**|(% colspan="2" %)**Register address**|(% colspan="2" %)**Data**|(% rowspan="2" %)**CRC check code**
89 +|**high byte**|**low byte**|**high byte**|**low byte**
90 90  |1 byte|06|1 byte|1 byte|1 byte|1 byte|2 bytes
91 91  
92 92  If the setting is successful, the original is returned
93 93  
94 -|=(% rowspan="2" style="width: 551px;" %)**There should be a message interval not less than 3.5 characters at the beginning**|=(% style="width: 114px;" %)**Address**|=(% style="width: 127px;" %)**Function code**|=(% style="width: 104px;" %)**Data**|=(% style="width: 180px;" %)**CRC check code**
94 +|(% rowspan="2" style="width:551px" %)**There should be a message interval not less than 3.5 characters at the beginning**|(% style="width:114px" %)**Address**|(% style="width:127px" %)**Function code**|(% style="width:104px" %)**Data**|(% style="width:180px" %)**CRC check code**
95 95  |(% style="width:114px" %)1 byte|(% style="width:127px" %)1 byte|(% style="width:104px" %)N bytes|(% style="width:180px" %)2 bytes
96 96  
97 -== (% style="color:inherit; font-family:inherit; font-size:26px" %)CRC check(%%) ==
97 +(% style="color:inherit; font-family:inherit; font-size:26px" %)**CRC check**
98 98  
99 99  The servo uses a 16-bit CRC check, and the host computer must also use the same check rule, otherwise the CRC check will make mistake. When transmitting, the low bit is in the front and the high bit is at the back. The CRC code are as follows:
100 100  
... ... @@ -165,6 +165,8 @@
165 165  
166 166  == **Communication example** ==
167 167  
168 +
169 +
168 168  **03 Function code read**
169 169  
170 170  Read the monitoring volume U0-31 bus voltage, the Modbus register address corresponding to this variable is 7716 (0x1E24)
... ... @@ -171,18 +171,20 @@
171 171  
172 172  Request format:
173 173  
174 -|=(% rowspan="2" %)**Address**|=(% rowspan="2" %)**Function code**|=(% colspan="2" %)**Register address**|=(% colspan="2" %)**Data**|=(% rowspan="2" %)**CRC check code**
175 -|=**high byte**|=**low byte**|=**high byte**|=**low byte**
176 +|(% rowspan="2" %)**Address**|(% rowspan="2" %)**Function code**|(% colspan="2" %)**Register address**|(% colspan="2" %)**Data**|(% rowspan="2" %)**CRC check code**
177 +|**high byte**|**low byte**|**high byte**|**low byte**
176 176  |01|03|1E|24|00|01|C2 29
177 177  
178 178  The slave responds normally:
179 179  
180 -|=(% rowspan="2" %)**Address**|=(% rowspan="2" %)**Function code**|=(% rowspan="2" %)**Number of bytes**|=(% colspan="2" %)**Data**|=(% rowspan="2" %)**CRC high byte**
181 -|=**high byte**|=**low byte**
182 +|(% rowspan="2" %)**Address**|(% rowspan="2" %)**Function code**|(% rowspan="2" %)**Number of bytes**|(% colspan="2" %)**Data**|(% rowspan="2" %)**CRC high byte**
183 +|**high byte**|**low byte**
182 182  |01|03|02|0C|4F|FC B0
183 183  
184 184  For example: The value read is 0x0C4F, which means that the voltage is 315.1V.
185 185  
188 +
189 +
186 186  **06 Function Code Write**
187 187  
188 188  P1-10 the maximum speed threshold is set to 3000rpm. This variable corresponds to the Modbus address: 266 (0x010A)
... ... @@ -189,14 +189,14 @@
189 189  
190 190  Request format:
191 191  
192 -|=(% rowspan="2" %)**Address**|=(% rowspan="2" %)**Function code**|=(% colspan="2" %)**Register address**|=(% colspan="2" %)**Data**|=(% rowspan="2" %)**CRC check code**
193 -|=**high byte**|=**low byte**|=**high byte**|=**low byte**
196 +|(% rowspan="2" %)**Address**|(% rowspan="2" %)**Function code**|(% colspan="2" %)**Register address**|(% colspan="2" %)**Data**|(% rowspan="2" %)**CRC check code**
197 +|**high byte**|**low byte**|**high byte**|**low byte**
194 194  |01|06|01|0A|0B|B8|AF, 76
195 195  
196 196  The slave responds normally:
197 197  
198 -|=(% rowspan="2" %)**Address**|=(% rowspan="2" %)**Function code**|=(% colspan="2" %)**Register address**|=(% colspan="2" %)**Data**|=(% rowspan="2" %)**CRC check code**
199 -|=**high byte**|=**low byte**|=**high byte**|=**low byte**
202 +|(% rowspan="2" %)**Address**|(% rowspan="2" %)**Function code**|(% colspan="2" %)**Register address**|(% colspan="2" %)**Data**|(% rowspan="2" %)**CRC check code**
203 +|**high byte**|**low byte**|**high byte**|**low byte**
200 200  |01|06|01|0A|0B|B8|AF, 76
201 201  
202 202  **10 Function code write**
... ... @@ -205,24 +205,23 @@
205 205  
206 206  Request format:
207 207  
208 -|=(% rowspan="2" %)**Address**|=(% rowspan="2" %)**Function code**|=(% colspan="2" %)**Initial address**|=(% colspan="2" %)**Number of register**|=(% rowspan="2" %)**Number of data**|=(% colspan="2" %)**Data 1**|=(% colspan="2" %)**Data 2**|=(% colspan="2" %)**CRC check code**
209 -|=**high byte**|=**low byte**|=**high byte**|=**low byte**|=**high byte**|=**low byte**|=**high byte**|=**low byte**|=**high byte**|=**low byte**
212 +|(% rowspan="2" %)**Address**|(% rowspan="2" %)**Function code**|(% colspan="2" %)**Initial address**|(% colspan="2" %)**Number of register**|(% rowspan="2" %)**Number of data**|(% colspan="2" %)**Data 1**|(% colspan="2" %)**Data 2**|(% colspan="2" %)**CRC check code**
213 +|**high byte**|**low byte**|**high byte**|**low byte**|**high byte**|**low byte**|**high byte**|**low byte**|**high byte**|**low byte**
210 210  |01|10|07|09|00|02|04|00|00|07|D0|16|59
211 211  
212 212  The slave responds normally:
213 213  
214 -|=(% rowspan="2" %)**Address**|=(% rowspan="2" %)**Function code**|=(% colspan="2" %)**Register address**|=(% colspan="2" %)**Data**|=(% colspan="2" %)**CRC check code**
215 -|=**high byte**|=**low byte**|=**high byte**|=**low byte**|=**high byte**|=**low byte**
218 +|(% rowspan="2" %)**Address**|(% rowspan="2" %)**Function code**|(% colspan="2" %)**Register address**|(% colspan="2" %)**Data**|(% colspan="2" %)**CRC check code**
219 +|**high byte**|**low byte**|**high byte**|**low byte**|**high byte**|**low byte**
216 216  |01|10|07|09|00|02|90|BE
217 217  
218 218  = **Servo communication parameter setting** =
219 219  
220 220  (% style="text-align:center" %)
221 -(((
222 -(% class="wikigeneratedid img-thumbnail" style="display:inline-block" %)
223 -[[Figure 8-3 Modbus communication parameter setting process>>image:image-20220608174504-2.png||id="Iimage-20220608174504-2.png"]]
224 -)))
225 +[[image:image-20220608174504-2.png]]
225 225  
227 +Figure 8-3 Modbus communication parameter setting process
228 +
226 226  **Set the servo address P12-1**
227 227  
228 228  When multiple servos are in network communication, each servo can only have a unique address, otherwise it will cause abnormal communication and fail to communicate.
... ... @@ -251,7 +251,7 @@
251 251  If you need to change the value of the function code frequently, it is recommended to turn off the function of real-time writing to EERPOM of function code, otherwise the EEPROM will be shortened due to frequent erasing and writing of the EEPROM.
252 252  
253 253  (% class="table-bordered" %)
254 -(% class="warning" %)|(% style="text-align:center; vertical-align:middle" %)[[image:image-20220611153214-3.png]]
257 +|(% style="text-align:center; vertical-align:middle" %)[[image:image-20220611153214-3.png]]
255 255  |After the EEPROM is damaged, the servo will have an non resettable fault!
256 256  
257 257  **Set the high and low order of the 32-bit monitoring data**
... ... @@ -272,20 +272,13 @@
272 272  Operation setting
273 273  )))|(% style="text-align:center; vertical-align:middle; width:165px" %)(((
274 274  Effective immediately
275 -)))|(% style="text-align:center; vertical-align:middle; width:109px" %)2|(% style="text-align:center; vertical-align:middle; width:85px" %)0 to 6|(% style="width:224px" %)(((
276 -0: 2400bps
277 -
278 -1: 4800bps
279 -
280 -2: 9600bps
281 -
282 -3: 19200bps
283 -
284 -4: 38400bps
285 -
286 -5: 57600bp
287 -
288 -6:115200bps
278 +)))|(% style="text-align:center; vertical-align:middle; width:109px" %)2|(% style="text-align:center; vertical-align:middle; width:85px" %)0 to 5|(% style="width:224px" %)(((
279 +* 0: 2400bps
280 +* 1: 4800bps
281 +* 2: 9600bps
282 +* 3: 19200bps
283 +* 4: 38400bps
284 +* 5: 57600bp
289 289  )))|(% style="text-align:center; vertical-align:middle; width:69px" %)-
290 290  |(% style="text-align:center; vertical-align:middle; width:121px" %)P12-03|(% style="text-align:center; vertical-align:middle; width:165px" %)Serial data format|(% style="text-align:center; vertical-align:middle; width:148px" %)(((
291 291  Operation setting
... ... @@ -292,13 +292,10 @@
292 292  )))|(% style="text-align:center; vertical-align:middle; width:165px" %)(((
293 293  Effective immediately
294 294  )))|(% style="text-align:center; vertical-align:middle; width:109px" %)0|(% style="text-align:center; vertical-align:middle; width:85px" %)0 to 3|(% style="width:224px" %)(((
295 -0: 1 stop bit, no parity
296 -
297 -1: 1 stop bit, odd parity
298 -
299 -2: 1 stop bit, even parity
300 -
301 -3: 2 stop bits, no parity
291 +* 0: 1 stop bit, no parity
292 +* 1: 1 stop bit, odd parity
293 +* 2: 1 stop bit, even parity
294 +* 3: 2 stop bits, no parity
302 302  )))|(% style="text-align:center; vertical-align:middle; width:69px" %)-
303 303  |(% style="text-align:center; vertical-align:middle; width:121px" %)P12-04|(% style="text-align:center; vertical-align:middle; width:165px" %)Modbus communication data is written into EEPROM|(% style="text-align:center; vertical-align:middle; width:148px" %)(((
304 304  Operation setting
... ... @@ -305,27 +305,13 @@
305 305  )))|(% style="text-align:center; vertical-align:middle; width:165px" %)(((
306 306  Effective immediately
307 307  )))|(% style="text-align:center; vertical-align:middle; width:109px" %)0|(% style="text-align:center; vertical-align:middle; width:85px" %)0 to 1|(% style="width:224px" %)(((
308 -0: Do not write to EEPROM, and do not store after power failure;
309 -
310 -1: Write to EEPROM, power-down storage.
301 +* 0: Do not write to EEPROM, and do not store after power failure;
302 +* 1: Write to EEPROM, power-down storage.
311 311  )))|(% style="text-align:center; vertical-align:middle; width:69px" %)-
312 -|P12-06|Modbus 32-bit variable big endian and little endian|(((
313 -Operation
314 314  
315 -setting
316 -)))|(((
317 -Effective
318 -
319 -immediately
320 -)))|0|0-1|(((
321 -0: Big-endian mode, the lower address stores the higher 16 bits of data, and the higher address stores the lower 16 bits of data
322 -
323 -1: Little-endian mode, the lower address stores the lower 16 bits of data, and the higher address stores the higher 16 bits of data
324 -)))|-
325 -
326 326  = **Modbus communication variable address and value** =
327 327  
328 -== **Variable address** ==
307 +== **Variable address description** ==
329 329  
330 330  Modbus registers are divided into two categories:
331 331  
... ... @@ -360,7 +360,7 @@
360 360  
361 361  For detailed parameter addresses, please refer to __[["11.1 Lists of parameters".>>https://docs.we-con.com.cn/bin/view/Servo/Manual/02%20VD2%20SA%20Series/11%20Appendix/#HListsofparameters]]__
362 362  
363 -== **Variable value type** ==
342 +== **Variable value type description** ==
364 364  
365 365  When writing function codes with signed numbers, you need to convert the pre-written data into hexadecimal complements. The conversion rules are as follows:
366 366