Query format in MODBUS RTU PROTOCOL

Hii
Pl send me
1. query format for Modbus RTU Protocol with ODD Parity.
2. If query goes to instrument using ODD Parity then how to do Error Checking? should it be based on Parity bit checking or based on CRC bits ckecking?
vijtin

Hii
Thanx for support but I have idea regarding error checking methods using Parity or CRC.
I want to know only query format in Modbus RTU protocol while sending Parity Bit (either odd or even).
With Parity None my query format is...
01 03 0001 0002 C40B
Where 01 is address of device
            03 is readcommand
            0001 is starting location
            0002 is length of data which i want to read
         & C40B is CRC
Same as above example what will be the query format with Parity EVEN or ODD?
Plz help me.....
vijtin

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Attachments:
MB_TCP.vi ‏29 KB
MB_PLC.vi ‏28 KB

Dear J,
Check the state machine Architecture here.
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Côté logiciel, nous sommes bien en retard...
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Notre HMI et programmé sous Vijéo.
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peut être partons nous dans une mauvaise direction.
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Error.jpg ‏1245 KB
modbusrecieve.jpg ‏1559 KB

what was the outcome of your debugging?
this is my situation:
I am having a timeout error (-1073807339) see attachment . I have stuck 100msec delays before and after the read visa with no change. I am attempting to communicate with an F4 controller with a very simple vi (using NI WATLOW drivers). I am starting a profile, aborting a profile, current step, current temp. I started my project by validating hardware and I used Watview as a sanity check. The communication path is F4D (RS485) / RS485 to RS232 converter /RS232 to USB converter /PXI chassis.
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