User guide

Communication protocol Serie30 Page 11/37
4.6 Function 6: MODBUS Single Register Write
This function has the same functionality as F16, but writes only 1 register.
• Function is implemented in devices Class.Group-Version = 5.20-10.XX and later
• A register contains 2 bytes (16 bit).
• Use this function for single configuration steps, cause the returned error is easily distinguishable from other register
writes.
• Note that single register operations are not allowed in the address ranges 0x03XX and 0xFFXX.
Request:
DevAddr 0x06 StAdd H StAdd L Data H Data L CRC16_L CRC16_H
Response:
DevAddr 0x06 StAdd H StAdd L Data H Data L CRC16_L CRC16_H
Error:
DevAddr 0x86 Error CRC16_L CRC16_H
Error codes:
2 Illegal data address
- address not accessible by function 6
- Start-address not defined (for writing)
3 Illegal data value
- frame length incorrect
4 Slave Device Failure
- The data written is outside the defined data range
4.7 Function 8: MODBUS Echo Test
This function may be used to perform a quick line check. It just returns the data received.
• Function is implemented in devices Class.Group-Version = 5.20-10.XX and later
• Data may be any 2 byte value
Request:
DevAddr 0x08 0x00 0x00 Data H Data L CRC16_L CRC16_H
Response:
DevAddr 0x08 0x00 0x00 Data H Data L CRC16_L CRC16_H
Error:
DevAddr 0x88 Error CRC16_L CRC16_H
Error codes:
3 Illegal data value:
- The data following the function code was not the fixed data (0x00, 0x00).