Data flow example
Process data communication example with default setting:
Word 1 | Word 2 | Word 3 | Word 4 | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| COB ID | D | DB | Byte 1 | Byte 2 | Byte 3 | Byte 4 | Byte 5 | Byte 6 | Byte 7 | Byte 8 | Description |
1 | 0x701 | Tx | 1 | "00" | – | – | – | – | – | – | – | BootUpMessage |
2 | 0x000 | Rx | 2 | "01" | "01" | – | – | – | – | – | – | Node start (operational) |
3 | 0x201 | Rx | 8 | "06" | "00" | "00" | "20" | "00" | "00" | "00" | "00" | Enable + setpoint speed |
4 | 0x080 | Rx | 0 | – | – | – | – | – | – | – | – | SYNC telegram |
5 | 0x181 | Tx | 8 | "C7" | "05" | "00" | "20" | "A2" | "00" | "28" | "00" | Process data object 1 |
6 | 0x281 | Tx | 8 | "29" | "09" | "00" | "00" | "01" | "1F" | "AC" | "0D" | Process data object 2 |
After a byte swap, the table looks as follows:
Word 4 | Word 3 | Word 2 | Word 1 | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| COB ID | D | DB | Byte 8 | Byte 7 | Byte 6 | Byte 5 | Byte 4 | Byte 3 | Byte 2 | Byte 1 | Description |
1 | 0x701 | Tx | 1 | – | – | – | – | – | – |
| "00" | BootUpMessage |
2 | 0x000 | Rx | 2 | – | – | – | – | – | – | "01" | "01" | Node start (operational) |
3 | 0x201 | Rx | 8 | "00" | "00" | "00" | "00" | "20" | "00" | "00" | "06" | Enable + setpoint speed (byte swap) |
4 | 0x080 | Rx | 0 | – | – | – | – | – | – | – | – | SYNC telegram |
5 | 0x181 | Tx | 8 | "00" | "28" | "00" | "A2" | "20" | "00" | "05" | "C7" | Process data object 1 |
6 | 0x281 | Tx | 8 | "0D" | "AC" | "1F" | "01" | "00" | "00" | "09" | "29" | Process data object 2 |
Explanation of the data:
Word 4 | Word 3 | Word 2 | Word 1 | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| COB ID | Explanation of the COB ID | Byte 8 | Byte 7 | Byte 6 | Byte 5 | Byte 4 | Byte 3 | Byte 2 | Byte 1 |
1 | 0x701 | BootUp message + device address 1 | – | – | – | – | – | – | – | Placeholder |
2 | 0x000 | NMT service | – | – | – | – | – | – | Bus status | Device address |
3 | 0x201 | Rx-PDO1 + device address 1 | – | – | Ramp specification | Setpoint speed | Control word | |||
4 | 0x080 | SYNC telegram | – | – | – | – | – | – | – | – |
5 | 0x181 | Tx PDO1 + device address | Output power | Output current | Actual speed | Status word | ||||
6 | 0x281 | Tx PDO2 + device address | Inverter temperature | IO status | Analog input 2 | Analog input 1 | ||||
Example of reading the index allocation by means of service device object (SDO):
Request controller → inverter (index: 1A00h)
Response inverter → controller: 10 00 01 21h → byte swap: 2101 00 10 h.
Explanation of the response:
→ 2101 = index in the manufacturer-specific object table
→ 00h = subindex
→ 10h = data width = 16 bit x 4 = 64 bit = 8 byte mapping length.
