Do All the CPU’s Support Modbus Protocol?
Yes, all the CPU’s in our range support Modbus RTU protocol as standard. Ethernet CPU’s also support Modbus/TCP protocol.
Modbus
What Programming Blocks Are Needed to Use CPU as Modbus Slave?
If you wish to use the CPU as a Modbus Slave then you do not need to use the Modbus Read/Write blocks. Most blocks and all IO points have a designated Modbus address. These can be found in the software User Manual or if in light-blue text next to the block within your program. SeeRead More
Can the CPU be a Modbus Master?
Yes, by use of the Modbus Read and Modbus Write blocks in the programming software.
Can CPU Act as a Modbus Master and Slave at the Same Time?
Yes, the CPU can act as both a Modbus Master and Slave at the same time but ONLY if they are on different communication ports. For example you may connect the CPU via RS232 programming lead to one of our HMI’s, and set it to act as a Modbus RTU Slave. At the same time,Read More
Do All Software Blocks Have a Modbus Address?
No, not all blocks have a direct Modbus address. For example On-Delay Timer setting does not have a direct address. However, you can use another reference block in your program to store the timer setting such as an AF or Counter block, which does have direct Modbus addresses.