Modbus Adressing

Please help with modbus adressing. How to read registers from a modbus card?

Modbus function code 3 is ‘read holding registers’ - so the first block of addresses should be
HR160 (0x00A0 in hex is 160 in decimal) and HR859 (0x35B).

The telecontrol command will be a coil (function code 5) so most likely either:
C12289 (0x3001) or C3001.

If you can’t find those particular addresses, try toggling the ‘One/Zero Based Addressing’ setting in the device’s configuration. If you get the holding registers connected and can’t write to them, try disabling ‘Allow Write Multiple Registers Request’ in the settings - function code 6 is specifically to write a single register, so the device may not support the (much more efficient) ‘Write Multiple Registers’ request.

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