Gambit

That is true when Z0 =40 on D30Z0 then it's D70. Z0 will probably be 11 sometimes. you can move any numer into Z0 the same as you would with a D register Strange maybe it's set from an HMI or something         

Just do the step i posted in your other post

Now lets change and let the System Q be the client. Then you need to change the basic parameter setting to user setting parameters Set the automat comms and refresh as you have set now. Now you are reading Coil 130 => D100.0 and writing coil 128 and 129 with the status from D200.0 and D200.1 So you code in the PLC schouls also be with hose devices where  Y80 - D100.0 Y81 - D200.0 Y82 - D200.1    

Ok First lets choose the first comm style with Factory IO being the client asking the questions. In this case all you have to to set the basic params and don't need the autom comm settings or Refresh. In this case Y80,Y81,Y82 reperesent Coil 128,129,130.  So If you set Coil 128 on Factory IO coil 130 should set as well.  

Check if there are any index writing going on Example: mov K0  D5Z0 if Z =50 then 0 is written into D55. Also stop any other comms possible writing to this devoce

I am not familiar with factory IO

But the code has nothing to to with the modbus devices when used as client  !! Why would it turn on  Also the basic paramter startup setting should be on user If you use the QJ71MT91 as a server than Y81 = Coil 128 If you use the QJ71MT91 as a Client than D200.0 = Coil 128 but you have to set user param

Core OS only support for the higher models I see. Just do the BOOTOS than 

This is from a previous post from @Integrator_99 made in GX Works 3  but i should work the same for GX Works 2 aswell 

Wouldnt it be scada which is the client (asking the questions) instead of server ? Also you are using D100 and D300 for reading and writing the modbus devices. When you write a value of 1 to D300 does the light come on   

Open GT designer Commuinication >  Write to memory card => TAB BOOROS/COREOS Write  First Write the core os and boot the HIM With that. Than the same for the BOOTOS procedure is mentioned in the TAB..  

The constant used in the example can also be an variable. Check the example of @pturmel  ...... MyArray[Index]  This doesnt have to be structued text it can be used in all editors    

Topper !!

You can download the latest version via your MyMitsubishi Account. V1.662 is the latest one i think