tabrez
Member
Hi Every one
1) I am using Quantum CPU 140 434 12A, Which has got two modbus comm ports,with XXMIT EFB and RS-232, i successfully communicate to the modbus device from modbus comm 1,But it is not working with the modbus comm port 2 even if i chaged port No. in the XXMIT EFB.
2)i Believe that these modbus comm ports can be used with both electrical media that is RS-232 and RS-485,as in the XXMIT instruction's command register BIT No.3 if i make it to 1 then the mode is RS-485 otherwise RS-232 default 0 (Zero) in that bit.
So i tried it using RS-485 with command register chaged to 1 in the Bit No. 3,but unfortunately it is not working at all and giving an error in the status register 129, offcourse the slave device i m using supports RS-485 MODBUS.
1) I am using Quantum CPU 140 434 12A, Which has got two modbus comm ports,with XXMIT EFB and RS-232, i successfully communicate to the modbus device from modbus comm 1,But it is not working with the modbus comm port 2 even if i chaged port No. in the XXMIT EFB.
2)i Believe that these modbus comm ports can be used with both electrical media that is RS-232 and RS-485,as in the XXMIT instruction's command register BIT No.3 if i make it to 1 then the mode is RS-485 otherwise RS-232 default 0 (Zero) in that bit.
So i tried it using RS-485 with command register chaged to 1 in the Bit No. 3,but unfortunately it is not working at all and giving an error in the status register 129, offcourse the slave device i m using supports RS-485 MODBUS.
