Currently we are communicating to Vishay Nobel weighscales (TAD 1) serially (Modbus ASCII) via a DB module.
However, these are now obsolete and it's replacement is the TAD 3 which cannot be communicated with using Modbus ASCII, only Modbus RTU.
Although there is a firmware download provided by Vishay Nobel which will allow limited functionality of Modbus ASCII (and would suffice for our needs) we have several units (most connected via Modbus ASCII and 1 connected by 4-20mA analogue input) and we would rather re-write the communications code to handle Modbus RTU, than start flashing the firmware depending on which weighscale fails.
A quick google has found that Prosoft provide a card to communicate with Modbus RTU but has anyone successfully connected a Modbus RTU device to PLC-5 and if so, how?
I'd like to avoid using a RB module if possible.
Steve
However, these are now obsolete and it's replacement is the TAD 3 which cannot be communicated with using Modbus ASCII, only Modbus RTU.
Although there is a firmware download provided by Vishay Nobel which will allow limited functionality of Modbus ASCII (and would suffice for our needs) we have several units (most connected via Modbus ASCII and 1 connected by 4-20mA analogue input) and we would rather re-write the communications code to handle Modbus RTU, than start flashing the firmware depending on which weighscale fails.
A quick google has found that Prosoft provide a card to communicate with Modbus RTU but has anyone successfully connected a Modbus RTU device to PLC-5 and if so, how?
I'd like to avoid using a RB module if possible.
Steve