- HMI Model: cMT-FHDX-220 (et al)
- EasyBuilder Pro Version: V6.10.01.252
- Serial Number: 2204105895 (et al)
Hi Team Weintek -
Our proprietary networked Slave device operates in both MODBUS RTU and BACnet MSTP modes, but only one mode at a given time.
We have need to “switch back and forth”, in a live operational sense, between MODBUS RTU and BACnet MS/TP protocols, with the Weintek HMI acting as a Dual-Protocol Master.
I am able to do this on the development bench using HMI COM2 for MODBUS RTU, and HMI COM3 for BACnet MSTP, by manually connecting only one of the two serial ports to our Slave device at any given time.
However, for usage beyond the development bench, we will need an automated or automation-assist method of switching between the two serial ports, so that only one of the two HMI serial COM ports is electrically or physically connected to our Slave(s) at a given time, to avoid RS485 bus contention/conflict between the two different protocol drivers.
Q1: Is there a programmatic way to independently, electrically enable/disable HMI serial ports COM2 (MODBUS RTU) and COM3 (BACnet MSTP) during runtime, so that we can make one COM port active and the other tri-state?
Q2: Conversely, is there a programmatic way to select, during runtime, which protocol driver (MODBUS RTU or BACnet MSTP) is active on the same com port at any given time, say using COM2?
I looked for something like this in the manual but did not find.
Context Note:
We are seeking this approach as a potential work-around as a result of the lack of Weintek BACnet driver support for BACnet objects BSV, CSV, PIV, as we have access to these internal device parameters via MODBUS RTU.
Thank you.
- Jim