No Communication?
- Verify RS232/RS485 wiring matches pinout
- Check baud rate, parity, stop bits
- Confirm correct device address
- Ensure master and slave configuration match
- Verify slave mode enabled on device
Connection Established but No Data?
- Confirm correct parameter/register addressing
- Verify data mapping between master and slave
- Check correct communication protocol settings
- Ensure polling from master is active
Intermittent or Unstable Communication?
- Check cable shielding and grounding
- Verify proper termination for RS485 network
- Inspect connectors for loose or damaged wiring
- Confirm stable power supply
Incorrect Data or Values?
- Verify correct register or parameter selection
- Check data type (bit, word, long)
- Confirm byte/word order
- Validate scaling or conversion
Read Works but Write Fails?
- Confirm slave allows write operations
- Check correct command format from master
- Verify register is writable
- Ensure proper timing between write commands
Slave Not Responding Properly?
- Verify slave configuration and addressing
- Restart slave device and communication interface
- Confirm firmware compatibility
- Test with minimal configuration
© HMS Networks AB 2025