I have a AO Smith / TOTEM CHP Unit, and we are interfacing with TCP/IP Modbus. I have all the values I would like to pick up (Flow & Return, Hours run etc) but there is a section named TOTEM finite state machine information. The input register is number 38 but it looks like a BACnet multistate module, but unable to use these in Modbus?
Here's an example
#3 - Engine Starting
#1 - Fault Check
#2 - IEEE waiting time when the mains if off
#3 - Reset step motor position