Goran Vuckovic

IVRD is used for reading inverters parameters from Mitsubishi VFDs. On other side, Mitsubishi PLC clones, usually do not support FROM and TO, and usually you need to use RD3A command. 

Hubs are Layer 1, switches are Layer 2 and there are Layer 3 switches/routers. I have connected many Q PLCs in my life, and if you connect them directly you need crossover except if your PC has Auto MDI-X, and it will have if it is Gigabit port. If you have problems connecting it with hub, just buy simple switch instead of hub and try it. Today switches are so cheap that it costs you or your company more to write all this posts than to try it. For example Tenda SG105, unmanaged , 5-port, Gigabit switch costs 10$.

I didn't understand your previous question, but I will try to explain. Q port doesn't support  Auto MDI-X so you will  need crossover cable to connect PC to PLC. Switches support  Auto MDI-X, so you can use either straigth or crossover cable. HUBs most likely do not support  Auto MDI-X, so you will likely need to have crossover cable from HUB to PLC.  Remember that idea is to connect PLC Transmit to PC Receive and PC Transmit to PLC Receive.

If you are connecting directly to Q port, than you need crossover, if you are connecting through switch than straigth cable is ok. It could be that with hub you need crossover cable.

Is VNC Server Function License installed? What is value of "Operating priority guaranteed time"?

There is small chance that multimeter or most measuring devices will detect changes with duration of 10ms.

I think that easiest method would be by using PLC inside function of A800, and adding one inductive proximity sensor for 0 degrees. After that everything would be more or less simple math.

Before start try to put parameters below to listed values: 77 - 2 (Parameter writing is enabled in any operation mode regardless of the operation status.) 550 - 5  Be sure that you are in NET mode. Then you can try command: FF0600090001   Also try FF0600080001 because I'm not certain is it +1 Modbus addressing.

For command 06  - Modbus Exception code 02 : "The data address received in the query is not an allowable address for the slave. More specifically, the combination of reference number and transfer length is invalid. For a controller with 100 registers, a request with offset 96 and length 4 would succeed, a request with offset 96 and length 5 will generate exception 02." For command 10 - Modbus Exception code 03: "A value contained in the query data field is not an allowable value for the slave.  This indicates a fault in the structure of remainder of a complex request, such as that the implied length is incorrect. It specifically does NOT mean that a data item submitted for storage in a register has a value outside the expectation of the application program, since the MODBUS protocol is unaware of the significance of any particular value of any particular register." It is 20h o'clock at my country, and I am going on dinner with my wife. We will continue tomorrow, and I will help you.

After that try this: FF06000A0001 000A is 40009

Try this: FF0300010003 and after that, try this: FF0300010010

Find attached InstallEtherway.zip

Yes, I have experience with A800 and Modbus. Why don't you send me the response from Etherway, and we could see a lot from that.

I've sent you DM.

  It has Modbus, CC-Link (all versions, Serial&Ethernet, IE, TSN), Profinet, Ethernet/IP, Mitsubishi Inverter Protocol, Profibus, Devicenet, CANopen, Controlnet, FL-Net, Lonworks, BACnet, SSCNet, EtherCAT. Some of them are standard, and some of them are as option. So Modbus is far from only protocol. About Modbus implementation, I am not 100% sure if it has Modbus FC23 Read/Write, but other than that I don't see how it is lame. There is one thing with Mitsubishi VFDs and that is that Parameters Number are practically always the same in last cca 35  years, on every model Mitsubishi is adding parameters not changing them, so you don't need to learn it again,  but it tends to be confusing for new guys. As remedy there is FR Configurator Software that helps a lot.