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Last modified by Wecon on 2025/09/03 21:04
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Wecon 1.1 1 = **EtherCAT Operation** =
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7 [[Figure 6-1 EtherCAT Operation Configuration Flow>>image:1687763900631-428.png]]
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13 = **EtherCAT Communication Fundamentals** =
14
15 == EtherCAT Communication Specifications ==
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17 |=**Hierarchy**|=**Content**|=**Specification**
18 |(% rowspan="3" %)Application layer|PDO|Variable PDO mapping
19 |SDO|SDO request, SDO reply
20 |CIA 402|(((
21 Cyclic Synchronous Position Mode(CSP)
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23 Origin return mode (HM)
24 )))
25 |(% rowspan="2" %)Physical layer|Transport protocol|100BASE-TX (IEEE802.3)
26 |Communication interface|RJ45 Port * 2 (IN, OUT)
27
28 == Communication Structure ==
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30 Wecon VD3E series bus servo drives adopt IEC 61800-7 (CiA402)-CANOpen motion control sub-protocol.
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35 (% style="display:inline-block" %)
36 [[Figure 6-2 Communication structure>>image:1687763990838-324.png]]
37 )))
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39
40 PDO (Process Data Object) is composed of Object Dictionary (Object Dictionary) which can be mapped in PDO, and the content of process data is defined according to PDO mapping.
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42 Email is a kind of aperiodic communication and can read and write all object dictionaries.
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44
45 == State Machine ==
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47 EtherCAT devices support four states and are responsible for coordinating the state relationship between master and slave applications at initialization and running:
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49 Init: Initialization, abbreviated as I;
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51 Pre-Operational: Pre-Operational, abbreviated as P;
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53 Safe-Operational: Safe operation, abbreviated as S;
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55 Operational: Operational, abbreviated as O.
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58 (% style="text-align:center" %)
59 (((
60 (% style="display:inline-block" %)
61 [[Figure 6-3 Communication structure>>image:企业微信截图_16877640707184.png]]
62 )))
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65 When changing from initialization state to operational state, it must be changed in the order of "initialization → pre-Operational → safe Operational → Operational"!
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67 Leapfrog transition when returning from operational state. Refer to the following table for state transition operation and initialization process:
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69 |=**Status**|=**Operate**
70 |Initialization|There is no communication in the application layer, and the master station can only read and write ESC registers
71 |Initialization → pre-operational|(((
72 The master station configures the site address of the slave station;
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74 Configure Email channels;
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76 Configure DC distributed clock;
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78 Request “pre-Operational" status
79 )))
80 |Pre-operation|Application Layer Email Data Communication (SDO)
81 |Pre-operation → safe operation|(((
82 The master station uses Email to initialize the process data mapping;
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84 The master station configures the SM channel used for process data communication;
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86 The main station is configured with FMMU;;
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88 Request "safe status"
89 )))
90 |Safe operation|Allow input data to be read without output signal (SDO, TPDO)
91 |Safe operation → operation|(((
92 The master station sends valid output data;
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94 Request “operation" status
95 )))
96 |Operation|Input and output are all valid and can use Email communication (SDO, TPDO, RPDO)
97
98 == Communication Indicator Lamp ==
99
100 The communication indicator for the VD3E servo drive is located on the CN5 (IN), CN6 (OUT) sockets, as shown INFigure 6-5As shown in.
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103 (% style="text-align:center" %)
104 (((
105 (% style="display:inline-block" %)
106 [[Figure 6-4 Communication indicator position>>image:1687764127429-364.png]]
107 )))
108
109
110 (1) Connection lamp (yellow)
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112 Used to display the status of CN5 and CN6 communication interfaces, and the display contents are shown in the following table.
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114 |=**Connection lamp status**|=**Explanation**
115 |OFF|The port is not connected to the network cable
116 |ON|The port is connected to the network cable
117
118 (2) Communication lamp (green)
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120 Used to display the status of CN5 and CN6 communication connections, as shown in the following table.
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122 |=**Connection lamp status**|=**Explanation**
123 |ON|No communication connection was established with the master station
124 |BLINKING|A communication connection has been established with the master station
125
126 == Process Data PDO ==
127
128 PDO outputs process data in real time. PDO can be divided into RPDO (for receiving instructions from master station) and TPDO (for feeding back its own status from slave station).
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133 (% style="display:inline-block" %)
134 [[Figure 6-6 PDO schematic diagram>>image:1687764189351-772.png]]
135 )))
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137
138 (1) PDO mapping parameters
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140 PDO mapping is used to establish the mapping relationship between object dictionary and PDO. 1600h-17FFh is RPDO, 1A00h-1BFFh is TPDO:
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142 |=**Name**|=**Parameter**|=**Nature**
143 |(% rowspan="2" %)RPDO|1600h|Variable mapping
144 |1701h ~~ 1705h|Fixed mapping
145 |(% rowspan="2" %)TPDO|1A00h|Variable mapping
146 |1B01h ~~ 1B04h|Fixed mapping
147
148 The following figure is an example of RxPDO mapping.
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150 (% style="text-align:center" %)
151 (((
152 (% style="display:inline-block" %)
153 [[Figure 6-7 Examples of RxPDO mapping>>image:1687764238838-148.png]]
154 )))
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156
157 The data type is defined as follows:
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159 |=**Data type**|=**Description**|=**Numerical range**
160 |SINT|Signed 8bit|-128 ~~ 127
161 |USINT|Unsigned 8bit|0 ~~ 255
162 |INT|Signed 16bit|-32768 ~~ 32767
163 |UINT|Unsigned 16bit|0~~65535
164 |DINT|Signed 32bit|-21247483648 ~~ 21247483647
165 |UDINT|Unsigned 32bit|0 ~~ 4294967295
166 |STRING|String Value|ASCII
167
168 The following figure is an example of TxPDO mapping.
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170 (% style="text-align:center" %)
171 (((
172 (% style="display:inline-block" %)
173 [[Figure 6-8 Examples of TxPDO mapping>>image:1687764276184-189.png]]
174 )))
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176
177 The following figure is an example of a SyncManager PDO mapping.
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179 (% style="text-align:center" %)
180 (((
181 (% style="display:inline-block" %)
182 [[Figure 6-8 SyncManager PDO Mapping Example>>image:1687764295841-774.png]]
183 )))
184
185
186 (2) Synchronize management of PDO allocation settings
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188 In EtherCAT periodic data communication, process data can contain multiple PDO mapping data objects. The data objects 0x1C10 ~~ Ox1C2F used in CoE protocol define the corresponding PDO mapping object list of SM (Synchronous Management Channel), and multiple PDO can be mapped in different sub-indexes.
189
190 |=**Index (hex)**|=**Sub-index (hex)**|=**Content**
191 |1C12|01|Choose to use one of 0x1600, 0x1701-0x1705 as the actual RPDO
192 |1C13|01|Select to use one of 0x1A00, 0x1B01-0x1B04 as the actual TPDO
193
194 (3) PDO configuration
195
196 The PDO mapping parameter contains a pointer to the PDO corresponding process data that the PDO needs to send or receive, including index, sub-index and mapping object length. The sub-index 0 records the number N of objects mapped by the PDO, and the length of each PDO data can reach 4N bytes at most, which can map one or more objects at the same time. Sub-index ~~ N is the mapping content. The mapping parameter content is defined as follows:
197
198 |=**Number of digits**|=**31**|=**...**|=**16**|=**15**|=**...**|=**8**|=**7**|=**...**|=**0**
199 |Description|(% colspan="3" %)Index|(% colspan="3" %)Sub-index|(% colspan="3" %)Object length
200
201 The index and sub-index together determine the position of the object in the object dictionary, and the object length indicates the specific bit length of the object (hexadecimal representation)
202
203 |Object length|bit length
204 |08h|8
205 |10h|16
206 |20h|32
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208 For example, the mapping parameter of 6040h-00 (control word) is 60400010h
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210 |(((
211 (% style="text-align:center" %)
212 [[image:1687764356036-174.png]]
213 )))
214 |(((
215 The PDO configuration can only be designed when the EtherCAT communication state machine is in pre-operation (Pro-Operation, panel display 2), otherwise an error will be reported.
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217 The PDO configuration parameters cannot be stored in the EEPROM. Therefore, after each power-on, please reconfigure the mapping object, otherwise, the mapping object is the default parameter of the drive
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219 The SDO fault codes are returned when:
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221 Modify PDO parameters in non-pre-operation state;
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223 Pre-write values other than 1600/1701 ~~ 1705 in 1C12; Values other than 1A00/1B01 ~~ 1B04 are pre-written in 1C13.
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225 **No more than 10 variable mappings can be added, otherwise the servo activation failure may occur.**
226 )))
227
228 == Email Data SDO ==
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230 EtherCAT Email data SDO is used to transmit aperiodic data, such as configuration of communication parameters, servo drive operation parameters and so on. EtherCAT's CoE service types include:
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232 (1) Emergency information; ② SDO request; ③ SDO response; ④ TxPDO; ⑤ RxPDO; ⑥ Remote TxPDO sending request; ⑦ Remote RxPDO sending request; ⑦ SDO information.
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234 Wecon VD3E series bus servo drives currently support ② SDO requests; ③ SDO response.
235
236 == Distributed Clock ==
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238 Distributed clock enables all EtherCAT devices to use the same system time, thus controlling the synchronous execution of tasks of each device. The slave station device can generate a synchronization signal according to the synchronized system time. Wecon VD3E series bus servo drives only support DC synchronous mode.
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240 (% style="text-align:center" %)
241 (((
242 (% style="display:inline-block" %)
243 [[Figure 6-9 DC Synchronous Mode Schematic Diagram>>image:企业微信截图_16877644223063.png]]
244 )))
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246
247
248 == Status Indication ==
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250 (% style="text-align:center" %)
251 (((
252 (% style="display:inline-block" %)
253 [[Figure 6-10 Status indication schema>>image:Servo pannel display.jpg||alt="1687764471147-216.png"]]
254 )))
255
256
257 **Description:**
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259 **(1) Communication connection status**
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261 The first digit tube from the left of the 5-bit LED indicator on the servo drive panel is used to display the connection status of the two Ethernet communication ports: upper "-" CN6 (OUT) and lower "-" CN5 (IN)
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263 Long dark: No communication connection detected
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265 Long Bright: A communication connection has been established
266
267 **(2) Communication Operating status**
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269 The servo drive panel of the 5-bit LED indicator lamp is the second digit tube from the left, which is used to display the EtherCAT state machine status of the slave station in character form.
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271 |**Panel display**|**Meaning**
272 |(((
273 (% style="text-align:center" %)
274 [[image:企业微信截图_16877645391823.png]]
275 )))|Initialization state
276 |(((
277 (% style="text-align:center" %)
278 [[image:企业微信截图_16877645542304.png]]
279 )))|Pre-operation status
280 |(((
281 (% style="text-align:center" %)
282 [[image:企业微信截图_16877645685788.png]]
283 )))|Safe operation status
284 |(((
285 (% style="text-align:center" %)
286 [[image:企业微信截图_16877645873434.png]]
287 )))|Operating status
288
289 **(3) Display of servo operation mode**
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291 Servo drive panel 5-bit LED indicator from the left of the third digit tube, used to display hexadecimal digital form display servo drive current operation mode.
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293 |**Panel display**|**Meaning**
294 |(((
295 (% style="text-align:center" %)
296 [[image:企业微信截图_16877646313948.png]]
297 )))|Contour position control mode
298 |(((
299 (% style="text-align:center" %)
300 [[image:企业微信截图_16877646502614.png]]
301 )))|Contour speed control mode
302 |(((
303 (% style="text-align:center" %)
304 [[image:企业微信截图_16877646869001.png]]
305 )))|Contour torque control mode
306 |(((
307 (% style="text-align:center" %)
308 [[image:企业微信截图_16877647056651.png]]
309 )))|Origin return mode
310 |(((
311 (% style="text-align:center" %)
312 [[image:企业微信截图_16877647411761.png]]
313 )))|Interpolation mode
314 |(((
315 (% style="text-align:center" %)
316 [[image:企业微信截图_1687764758384.png]]
317 )))|Cyclic Synchronous Position mode
318 |(((
319 (% style="text-align:center" %)
320 [[image:企业微信截图_16877647747873.png]]
321 )))|Periodic synchronous speed mode
322 |(((
323 (% style="text-align:center" %)
324 [[image:企业微信截图_1687764789355.png]]
325 )))|Periodic synchronous torque mode
326
327 (4)**Servo status display**
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329 Servo drive panel 5-bit LED indicator from the left of the fourth and fifth digit tube, used to display the servo status of the slave station.
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331 |**Panel display**|**Meaning**
332 |(((
333 (% style="text-align:center" %)
334 [[image:企业微信截图_16877648316610.png]]
335 )))|Not ready nr
336 |(((
337 (% style="text-align:center" %)
338 [[image:企业微信截图_16877648448112.png]]
339 )))|Get ready ry
340 |(((
341 (% style="text-align:center" %)
342 [[image:企业微信截图_1687764861143.png]]
343 )))|Run rn
344 |(((
345 (% style="text-align:center" %)
346 [[image:企业微信截图_16877648784506.png]]
347 )))|Failure-free nF
348
349 == Introduction to CiA402 Control ==
350
351 The use of Wecon VD3E Series Bus Type servo drives must be guided according to the procedure specified in Standard 402 Protocol.
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353 (% style="text-align:center" %)
354 (((
355 (% style="display:inline-block" %)
356 [[Figure 6-11 CiA402 state machine switching schema>>image:1687765004268-447.png]]
357 )))
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359
360
361 |=**Status**|=**Description**
362 |Initialization|(((
363 Drive initialization, internal self-test has completed.
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365 Parameters cannot be set, and servo drive function cannot be performed.
366 )))
367 |Servo trouble-free|(((
368 There is no fault in the servo drive.
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370 Parameters can be set.
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372 |Servo ready|(((
373 Servo drives are ready.
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375 Parameters can be set.
376 )))
377 |Wait to turn on servo enable|(((
378 The servo drive waits to turn on the servo enable.
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380 Parameters can be set.
381 )))
382 |Servo operation|The servo drive is running normally.
383 |Quick stop|(((
384 The servo drive is performing the quick shutdown function.
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386 Only function codes with the attribute "Run valid" can be set.
387 )))
388 |Malfunction shutdown|(((
389 The servo drive is performing the fault shutdown function.
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391 Only function codes with the attribute "Run valid" can be set.
392 )))
393 |Fault|(((
394 Failure shutdown is complete, and all drive functions are disabled.
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396 Allow parameters to be changed to troubleshoot.
397 )))
398
399 == Basic Characteristics ==
400
401 The EtherCAT network cable is connected to the CN5 (IN), CN6 (OUT) interfaces, and its electrical characteristics conform to IEEE 802.3 standard.
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403 (% style="text-align:center" %)
404 (((
405 (% style="display:inline-block; width:714px;" %)
406 [[Figure 6-12 Communication port>>image:1687767552529-985.png||height="327" width="714"]]
407 )))
408
409
410 |=**Pin**|=**Name**|=**Function description**
411 |1|TX+|Sending data+
412 |2|TX-|Sending data-
413 |3|RX+|Receiving data+
414 |4|-|-
415 |5|-|-
416 |6|RX-|Receiving data-
417 |7|-|-
418 |8|-|-
419
420 EtherCAT communication topology connections are very flexible, taking linear connections and ring connections as examples:
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422 (% style="text-align:center" %)
423 (((
424 (% style="display:inline-block" %)
425 [[Figure 6-13 Linear connection>>image:1687765312978-447.png]]
426 )))
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429 (% style="text-align:center" %)
430 (((
431 (% style="display:inline-block" %)
432 [[Figure 6-114 Ring connection>>image:1687765334875-824.png]]
433 )))