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Changes for page 08 Communication

Last modified by Iris on 2025/07/24 15:23
From version 4.12
edited by Stone Wu
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To version 9.1
edited by Stone Wu
on 2022/08/30 09:58
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1 -Servo.1 User Manual.02 VD2 SA Series.WebHome
1 +Servo.Manual.02 VD2 SA Series.WebHome
Content
... ... @@ -11,7 +11,7 @@
11 11  
12 12  Figure 8-1 The position of RS485 communication port of VD2B drive
13 13  
14 -For the position of the RS485 communication port of other models, see __[[4.5 Communication signal wiring>>https://docs.we-con.com.cn/bin/view/Servo/2.%20User%20Manual/06%20VD2%20SA%20Series%20Servo%20Drives%20Manual%20%28Full%20V1.1%29/04%20Wiring/#HCommunicationsignalwiring]]__.
14 +For the position of the RS485 communication port of other models, see __[[4.5 Communication signal wiring>>https://docs.we-con.com.cn/bin/view/Servo/Manual/02%20VD2%20SA%20Series/04%20Wiring/#HCommunicationsignalwiring]]__.
15 15  
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  
... ... @@ -45,7 +45,7 @@
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  
47 47  (% class="table-bordered" %)
48 -|(% rowspan="2" 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**
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 51  == **Description of supported function codes** ==
... ... @@ -53,7 +53,7 @@
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  
55 55  (% class="table-bordered" %)
56 -|(% style="text-align:center; vertical-align:middle" %)**Operate**|(% style="text-align:center; vertical-align:middle" %)**Command code**
56 +|=(% style="text-align: center; vertical-align: middle;" %)**Operate**|=(% style="text-align: center; vertical-align: middle;" %)**Command code**
57 57  |(% style="text-align:center; vertical-align:middle" %)Read 16-bit/32-bit function code|(% style="text-align:center; vertical-align:middle" %)0x03
58 58  |(% style="text-align:center; vertical-align:middle" %)Write 16-bit function code|(% style="text-align:center; vertical-align:middle" %)0x06
59 59  |(% style="text-align:center; vertical-align:middle" %)Write 32-bit function code|(% style="text-align:center; vertical-align:middle" %)0x10
... ... @@ -68,9 +68,10 @@
68 68  
69 69  Correct response format:
70 70  
71 -|(% rowspan="2" %)**Address**|(% rowspan="2" %)**Function code**|(% rowspan="2" %)**Number of bytes of returned data**|(% colspan="2" %)**Register 1**|(% rowspan="2" %)**…**|(% rowspan="2" %)**CRC check code**
72 -|**high byte**|**low byte**
73 -|1 byte|03|1 byte|1 byte|1 byte|…|2 bytes
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**
74 +|1 byte|03|(% style="width:279px" %)1 byte|(% style="width:160px" %)1 byte|(% style="width:114px" %)1 byte|(% style="width:98px" %)…|2 bytes
74 74  
75 75  **Write function code: 0x06**
76 76  
... ... @@ -90,8 +90,8 @@
90 90  
91 91  If the setting is successful, the original is returned
92 92  
93 -|(% rowspan="2" %)**There should be a message interval not less than 3.5 characters at the beginning**|**Address**|**Function code**|**Data**|**CRC check code**
94 -|1 byte|1 byte|N bytes|2 bytes
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 +|(% style="width:114px" %)1 byte|(% style="width:127px" %)1 byte|(% style="width:104px" %)N bytes|(% style="width:180px" %)2 bytes
95 95  
96 96  (% style="color:inherit; font-family:inherit; font-size:26px" %)**CRC check**
97 97  
... ... @@ -150,13 +150,13 @@
150 150  == **Error response frame** ==
151 151  
152 152  (% class="table-bordered" %)
153 -|(% style="text-align:center; vertical-align:middle" %)**Address**|(% style="text-align:center; vertical-align:middle" %)**Function code**|(% style="text-align:center; vertical-align:middle" %)**Error code**|(% style="text-align:center; vertical-align:middle" %)**CRC check code**
154 +|=(% style="text-align: center; vertical-align: middle;" %)**Address**|=(% style="text-align: center; vertical-align: middle;" %)**Function code**|=(% style="text-align: center; vertical-align: middle;" %)**Error code**|=(% style="text-align: center; vertical-align: middle;" %)**CRC check code**
154 154  |(% style="text-align:center; vertical-align:middle" %)1 byte|(% style="text-align:center; vertical-align:middle" %)Command code+0x80|(% style="text-align:center; vertical-align:middle" %)Error code|(% style="text-align:center; vertical-align:middle" %)2 bytes
155 155  
156 156  When an error occurs, set the function code bit7 issued by the host to 1, and return (for example, 0x03 returns 0x83, 0x06 returns 0x86); the description of the error code are as follows.
157 157  
158 158  (% class="table-bordered" %)
159 -|(% style="text-align:center; vertical-align:middle" %)**Error code**|(% style="text-align:center; vertical-align:middle" %)**Coding description**
160 +|=(% style="text-align: center; vertical-align: middle;" %)**Error code**|=(% style="text-align: center; vertical-align: middle;" %)**Coding description**
160 160  |(% style="text-align:center; vertical-align:middle" %)0x0001|(% style="text-align:center; vertical-align:middle" %)Illegal command code
161 161  |(% style="text-align:center; vertical-align:middle" %)0x0002|(% style="text-align:center; vertical-align:middle" %)Illegal data address
162 162  |(% style="text-align:center; vertical-align:middle" %)0x0003|(% style="text-align:center; vertical-align:middle" %)Illegal data
... ... @@ -202,6 +202,22 @@
202 202  |**high byte**|**low byte**|**high byte**|**low byte**
203 203  |01|06|01|0A|0B|B8|AF, 76
204 204  
206 +**10 Function code write**
207 +
208 +P07-09 set the 1st segment position to 2000, and this variable corresponds to the Modbus address: 1801 (0x0709).
209 +
210 +Request format:
211 +
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**
214 +|01|10|07|09|00|02|04|00|00|07|D0|16|59
215 +
216 +The slave responds normally:
217 +
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**
220 +|01|10|07|09|00|02|90|BE
221 +
205 205  = **Servo communication parameter setting** =
206 206  
207 207  (% style="text-align:center" %)
... ... @@ -209,29 +209,26 @@
209 209  
210 210  Figure 8-3 Modbus communication parameter setting process
211 211  
212 -**(1) Set the servo address P12-1**
229 +**Set the servo address P12-1**
213 213  
214 214  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.
215 215  
216 -**(2) Set the serial port baud rate P12-2**
233 +**Set the serial port baud rate P12-2**
217 217  
218 218  The communication rate of the servo and the communication rate of the host computer must be set consistently, otherwise the communication cannot be carried out.
219 219  
220 -**(3) Set the serial port data format P12-3**
237 +**Set the serial port data format P12-3**
221 221  
222 222  The data bit check methods of servo communication are:
223 223  
224 -Odd parity
241 +* Odd parity
242 +* Even parity
243 +* No parity
244 +* The stop bit: 1 stop bit and 2 stop bits.
225 225  
226 -Even parity
227 -
228 -No parity
229 -
230 -The stop bit: 1 stop bit and 2 stop bits.
231 -
232 232  The data frame format of the servo and the host computer must be consistent, otherwise the communication cannot be carried out.
233 233  
234 -**(4) Set that whether the function code changed by Modbus communication is written into EEPROM in real time [P12-4]**
248 +**Set that whether the function code changed by Modbus communication is written into EEPROM in real time [P12-4]**
235 235  
236 236  When the host computer modifies the servo function code through communication, it can choose to store it in EEPROM in real time, which has the function of power-off storage.
237 237  
... ... @@ -243,7 +243,7 @@
243 243  |(% style="text-align:center; vertical-align:middle" %)[[image:image-20220611153214-3.png]]
244 244  |After the EEPROM is damaged, the servo will have an non resettable fault!
245 245  
246 -**(5) Set the high and low order of the 32-bit monitoring data**
260 +**Set the high and low order of the 32-bit monitoring data**
247 247  
248 248  Part of the monitoring volume is 32-bit length and occupies 2 consecutive bias numbers. The user needs to set the order of the data high bit and low bit correctly, otherwise it will cause data reading and writing errors!
249 249  
... ... @@ -252,51 +252,42 @@
252 252  The description of related function codes are as follows.
253 253  
254 254  (% class="table-bordered" %)
255 -|(% style="text-align:center; vertical-align:middle; width:121px" %)**Function code**|(% style="text-align:center; vertical-align:middle; width:205px" %)**Name**|(% style="text-align:center; vertical-align:middle; width:187px" %)(((
269 +|=(% style="text-align: center; vertical-align: middle; width: 121px;" %)**Function code**|=(% style="text-align: center; vertical-align: middle; width: 165px;" %)**Name**|=(% style="text-align: center; vertical-align: middle; width: 148px;" %)(((
256 256  **Setting method**
257 -)))|(% style="text-align:center; vertical-align:middle; width:186px" %)(((
271 +)))|=(% style="text-align: center; vertical-align: middle; width: 165px;" %)(((
258 258  **Effective time**
259 -)))|(% style="text-align:center; vertical-align:middle; width:130px" %)**Default value**|(% style="text-align:center; vertical-align:middle; width:132px" %)**Range**|(% style="text-align:center; vertical-align:middle; width:335px" %)**Definition**|(% style="text-align:center; vertical-align:middle; width:189px" %)**Unit**
260 -|(% style="text-align:center; vertical-align:middle; width:121px" %)P12-02|(% style="text-align:center; vertical-align:middle; width:205px" %)Baud rate|(% style="text-align:center; vertical-align:middle; width:187px" %)(((
273 +)))|=(% style="text-align: center; vertical-align: middle; width: 109px;" %)**Default value**|=(% style="text-align: center; vertical-align: middle; width: 85px;" %)**Range**|=(% style="text-align: center; vertical-align: middle; width: 224px;" %)**Definition**|=(% style="text-align: center; vertical-align: middle; width: 69px;" %)**Unit**
274 +|(% style="text-align:center; vertical-align:middle; width:121px" %)P12-02|(% style="text-align:center; vertical-align:middle; width:165px" %)Baud rate|(% style="text-align:center; vertical-align:middle; width:148px" %)(((
261 261  Operation setting
262 -)))|(% style="text-align:center; vertical-align:middle; width:186px" %)(((
276 +)))|(% style="text-align:center; vertical-align:middle; width:165px" %)(((
263 263  Effective immediately
264 -)))|(% style="text-align:center; vertical-align:middle; width:130px" %)2|(% style="text-align:center; vertical-align:middle; width:132px" %)0 to 5|(% style="width:335px" %)(((
265 -0-2400bps
266 -
267 -1-4800bps
268 -
269 -2-9600bps
270 -
271 -3-19200bps
272 -
273 -4-38400bps
274 -
275 -5-57600bp
276 -)))|(% style="text-align:center; vertical-align:middle; width:189px" %)-
277 -|(% style="text-align:center; vertical-align:middle; width:121px" %)P12-03|(% style="text-align:center; vertical-align:middle; width:205px" %)Serial data format|(% style="text-align:center; vertical-align:middle; width:187px" %)(((
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
285 +)))|(% style="text-align:center; vertical-align:middle; width:69px" %)-
286 +|(% 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" %)(((
278 278  Operation setting
279 -)))|(% style="text-align:center; vertical-align:middle; width:186px" %)(((
288 +)))|(% style="text-align:center; vertical-align:middle; width:165px" %)(((
280 280  Effective immediately
281 -)))|(% style="text-align:center; vertical-align:middle; width:130px" %)0|(% style="text-align:center; vertical-align:middle; width:132px" %)0 to 3|(% style="width:335px" %)(((
282 -0: 1 stop bit, no parity
283 -
284 -1: 1 stop bit, odd parity
285 -
286 -2: 1 stop bit, even parity
287 -
288 -3: 2 stop bits, no parity
289 -)))|(% style="text-align:center; vertical-align:middle; width:189px" %)-
290 -|(% style="text-align:center; vertical-align:middle; width:121px" %)P12-04|(% style="text-align:center; vertical-align:middle; width:205px" %)Modbus communication data is written into EEPROM|(% style="text-align:center; vertical-align:middle; width:187px" %)(((
290 +)))|(% 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" %)(((
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
295 +)))|(% style="text-align:center; vertical-align:middle; width:69px" %)-
296 +|(% 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" %)(((
291 291  Operation setting
292 -)))|(% style="text-align:center; vertical-align:middle; width:186px" %)(((
298 +)))|(% style="text-align:center; vertical-align:middle; width:165px" %)(((
293 293  Effective immediately
294 -)))|(% style="text-align:center; vertical-align:middle; width:130px" %)0|(% style="text-align:center; vertical-align:middle; width:132px" %)0 to 1|(% style="width:335px" %)(((
295 -0: Do not write to EEPROM, and do not store after power failure;
300 +)))|(% 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" %)(((
301 +* 0: Do not write to EEPROM, and do not store after power failure;
302 +* 1: Write to EEPROM, power-down storage.
303 +)))|(% style="text-align:center; vertical-align:middle; width:69px" %)-
296 296  
297 -1: Write to EEPROM, power-down storage.
298 -)))|(% style="text-align:center; vertical-align:middle; width:189px" %)-
299 -
300 300  = **Modbus communication variable address and value** =
301 301  
302 302  == **Variable address description** ==
... ... @@ -303,24 +303,21 @@
303 303  
304 304  Modbus registers are divided into two categories:
305 305  
306 -~1. The first category is servo function code parameters (address: 0x0001 to 0x0D08), this part of the register is readable and writable (that is, 0x03 and 0x06 are supported);
311 +1. The first category is servo function code parameters (address: 0x0001 to 0x0D08), this part of the register is readable and writable (that is, 0x03 and 0x06 are supported);
312 +1. The second category is the monitoring volume of the servo (address: 0x1E01 to 0x2010), this part of the register is only readable (0x03 function is supported).
307 307  
308 -2. The second category is the monitoring volume of the servo (address: 0x1E01 to 0x2010), this part of the register is only readable (0x03 function is supported).
309 -
310 310  **Servo function code representation: PXX-YY.**
311 311  
312 -XX: represents the function code group number,
316 +* XX: represents the function code group number,
317 +* YY: represents the bias within the function code group;;
313 313  
314 -YY: represents the bias within the function code group;;
315 -
316 316  During servo communication, the communication address of the function code is a 16-bit address, which is composed of the function code group number (high 8 bits) + group bias (low 8 bits), for example, the Modbus address corresponding to P12-1 (servo address) is 0x0C01.
317 317  
318 318  **Servo monitor volume representation: Uxx-yy.**
319 319  
320 -xx: represents the monitoring volume group number,
323 +* xx: represents the monitoring volume group number,
324 +* yy: represents the bias within the monitoring volume group;
321 321  
322 -yy: represents the bias within the monitoring volume group;
323 -
324 324  During Modbus communication, the starting address of the monitoring volume is 0x1E01, and the conversion relationship of the address is similar to the representation way of the function code.
325 325  
326 326  For example, U0-01 (servo status) corresponds to the Modbus address is 0x1E01.
... ... @@ -328,35 +328,33 @@
328 328  In order to facilitate actual use, this manual provides both decimal and hexadecimal address identification, it is shown in the following table:
329 329  
330 330  (% class="table-bordered" %)
331 -|(% style="text-align:center; vertical-align:middle" %)**Function code**|(% style="text-align:center; vertical-align:middle" %)(((
332 -**Modbus address**
333 +|=(% style="text-align: center; vertical-align: middle; width: 162px;" %)**Function code**|=(% style="text-align: center; vertical-align: middle; width: 302px;" %)(((
334 +**Modbus address (Hexadecimal)**
335 +)))|=(% style="text-align: center; vertical-align: middle; width: 278px;" %)(((
336 +**Modbus address (Decimal)**
337 +)))|=(% style="text-align: center; vertical-align: middle; width: 192px;" %)**Category**|=(% style="text-align: center; vertical-align: middle; width: 142px;" %)**Name**
338 +|(% style="text-align:center; vertical-align:middle; width:162px" %)P0-1|(% style="text-align:center; vertical-align:middle; width:302px" %)0x0001|(% style="text-align:center; vertical-align:middle; width:278px" %)1|(% style="text-align:center; vertical-align:middle; width:192px" %)Basic settings|(% style="text-align:center; vertical-align:middle; width:142px" %)Control mode
333 333  
334 -**(Hexadecimal)**
335 -)))|(% style="text-align:center; vertical-align:middle" %)(((
336 -**Modbus address**
340 +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]]__
337 337  
338 -**(Decimal)**
339 -)))|(% style="text-align:center; vertical-align:middle" %)**Category**|(% style="text-align:center; vertical-align:middle" %)**Name**
340 -|(% style="text-align:center; vertical-align:middle" %)P0-1|(% style="text-align:center; vertical-align:middle" %)0x0001|(% style="text-align:center; vertical-align:middle" %)1|(% style="text-align:center; vertical-align:middle" %)Basic settings|(% style="text-align:center; vertical-align:middle" %)Control mode
341 -
342 -For detailed parameter addresses, please refer to __[["11.1 Lists of parameters".>>https://docs.we-con.com.cn/bin/view/Servo/2.%20User%20Manual/06%20VD2%20SA%20Series%20Servo%20Drives%20Manual%20%28Full%20V1.1%29/11%20Appendix/#HListsofparameters]]__
343 -
344 344  == **Variable value type description** ==
345 345  
346 346  When writing function codes with signed numbers, you need to convert the pre-written data into hexadecimal complements. The conversion rules are as follows:
347 347  
348 -~1. The data is positive or 0: complement code = original code
346 +1. The data is positive or 0: complement code = original code
347 +1. The data is negative: complement code = 0xFFFF-absolute value of data + 0x0001
349 349  
350 -2. The data is negative: complement code = 0xFFFF-absolute value of data + 0x0001
349 +For example:
351 351  
352 -For example,The 16-bit signed positive number +100, the original code is 0x0064, and the complement is: 0x0064. The 16-bit signed positive number -100, its hexadecimal complement is: 0xFFFF-0x0064 + 0x0001 = 0xFF9C.
351 +* The 16-bit signed positive number +100, the original code is 0x0064, and the complement is: 0x0064.
352 +* The 16-bit signed positive number -100, its hexadecimal complement is: 0xFFFF-0x0064 + 0x0001 = 0xFF9C.
353 +* If it is an unsigned number, just pass it directly according to its original code. For example, if the decimal number is 32768, write 0x8000 directly.
353 353  
354 -If it is an unsigned number, just pass it directly according to its original code. For example, if the decimal number is 32768, write 0x8000 directly.
355 -
356 356  == **Numerical unit description** ==
357 357  
358 358  Some values have units and decimals, such as 0.1%, 0.1Hz, 0.01ms, and the corresponding value conversion is required when reading and writing. The methods are as follows:
359 359  
360 -~1. When the unit is 0.1%: 1 represents 0.1%, 10 represents 1.0%, 1000 represents 100.0%. Therefore, writing 1000 means setting to 100.0%; on the contrary, if it is reading 1000, it means that the value is 100.0%;
359 +1. When the unit is 0.1%: 1 represents 0.1%, 10 represents 1.0%, 1000 represents 100.0%. Therefore, writing 1000 means setting to 100.0%; on the contrary, if it is reading 1000, it means that the value is 100.0%;
360 +1. When the unit is 0.01ms: 1 means 0.01ms, 50 means 0.5ms, 10000 means 100ms. Therefore, writing 1000 means setting to 10.00ms; on the contrary, if 1000 is read, it means 10.00ms;
361 361  
362 -2. When the unit is 0.01ms: 1 means 0.01ms, 50 means 0.5ms, 10000 means 100ms. Therefore, writing 1000 means setting to 10.00ms; on the contrary, if 1000 is read, it means 10.00ms; The other units can be deduced by this, and integer remains unchanged.
362 +The other units can be deduced by this, and integer remains unchanged.