I think that limitation comes from PL7 ter port / firmware, because max number of integers should be 125.
http://modbus.control.com/thread/1249550734
Also from twido PLC I can read 125 integers at one time, with same cable, which I used with PL7 (TSX PSX1031).
I only downloaded your program to PLC, and then I put PLC to Run mode. I didn't do anything to your PLC test program, it works as it is now.
I noticed that you data format is selected to binary, change it. Even that if communication works you should see values on binary format now. (there should be 1 still on at modbuss address 40001 or 400001.
http://modbus.control.com/thread/1249550734
Also from twido PLC I can read 125 integers at one time, with same cable, which I used with PL7 (TSX PSX1031).
I only downloaded your program to PLC, and then I put PLC to Run mode. I didn't do anything to your PLC test program, it works as it is now.
I noticed that you data format is selected to binary, change it. Even that if communication works you should see values on binary format now. (there should be 1 still on at modbuss address 40001 or 400001.