QJ71MB91 Modbus Card - Read Input Registers

[marin4]

Hi, I have a QJ71MB91 Modbus Card setup as a slave on Channel 1 - RS232 - Slave ID 1

I have a laptop setup as a Modbus Master and all is working for Holding Registers, Coil Status, Input Status.

But when I try to Read Input Registers, I just get an error on the Modbus Master and the error light comes on the QJ71MB91 Card.

In Modbus Device Assignment - all was configured  except for Input Register that just shows 0 / 0 - I have tried D2000 / 100  (Holding Registers is D0 / 500).

I have tried to Read Input Register (FC=04) 30001 / 32000 etc - but just receive errors.

I'm using GX Works 2 latest version - does anyone know how to get this working or have a some sample code.

Thanks

Mike.

[marin4]

Fixed the problem now.

In Switch Settings select User Setting Parameter otherwise the settings in Modbus Device Assignment Parameter are not downloaded to the QJ71MB91 card and it just uses the defaults out of the box !

Thanks to  Rafi at Mitsubishi for getting this sorted.

Mike.