interface citect scada to modbus rtu


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i built modbus rtu like in using pic16f877a.
i test rtu using modbus test program its work ok
i read address for modbus rtu, read-write data to address 40001, 40002, etc

in citect scada v6.0 i built small project around address 40001 as variable tag...

for communication in citect i select express wizard then--->ioserver-->iodev-->external memory device-->for driver i select modicon 484 serial (modbus binary protocol). then drive address 1 as in my rtu (1) then com1 for port communication. then i fill all data needed for I/O servers...Boards...Ports...I/O Devices. i test my project using Disc I/o devices its work fine.

i do some modification for citect.ini [MODBUS]InitType....[MODBUS]MaxBits

after that do real test with rtu i compile project ok. then run project its pass without any error but when i go to page in run time i just see.(#com) and then hardware alarm (plc server I/o device off line.

my question when i select modicon 484 modbus serial (modbus binary protocol) for driver is wrong?

any one interface that rtu to citect scada before?

any help pls.
any one wanna share information my email
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