SDO communication from the PLC
ADS blocks are used for SDO communication from the PLC. These function blocks can be used for sending SDO telegrams and receiving the response of the slave (ADSWRITE/ADSREAD).
Input parameters | Description |
|---|---|
NETID | ADS NetID of the CAN interface |
Port number | 0x1000hex + NodeId (slave number) |
IDXGRP | SDO Index |
IDXOFFS | SDO Subindex |
LEN | Length of SDO data (1...4) |
Manual network management
The CANopen state (STOPPED, PRE-OPERATIONAL, OPERATIONAL) of a CANopen slave can be changed via ADS write control. In this case the AMS address should be set as for SDO communication. The other parameter are listed in the following table:
|
ADS State |
Device State |
CANopen state transition |
|
ADSSTATE_RUN (5) |
0 |
OP->PREOP |
|
ADSSTATE_RUN (5) |
1 |
PREOP->OP |
|
ADSSTATE_STOP (6) |
0 |
OP->STOP |
|
ADSSTATE_RUN (5) |
1 |
STOP->OP (with communication reset) |
|
ADSSTATE_RUN (5) |
3 |
STOP->OP (without communication reset) |
|
ADSSTATE_STOP (6) |
0 |
PREOP->STOP |
|
ADSSTATE_RUN (5) |
2 |
STOP->PREOP (without communication reset) |
Restarting the CAN interface
The ADSWRTCTL function block can be used to stop and restart the CAN interface. It should be stopped first before restarting it.
Input parameters | Description |
|---|---|
NETID | ADS NetID of the CAN interface |
Port number | 200dec |
ADSSTATE | ADSSTATE_STOP, ADSSTATE_RUN |
DEVSTATE | 0 |
LEN | 0 |
SRCADDR | 0 |