Reading & processing of HDLC data from 25 pin serial port
Reading & processing of HDLC data from 25 pin serial port
Reading & processing of HDLC data from 25 pin serial port
Reading & processing of HDLC data from 25 pin serial port
Reading & processing of HDLC data from 25 pin serial port
Reading & processing of HDLC data from 25 pin serial port Reading & processing of HDLC data from 25 pin serial port Reading & processing of HDLC data from 25 pin serial port Reading & processing of HDLC data from 25 pin serial port Reading & processing of HDLC data from 25 pin serial port Reading & processing of HDLC data from 25 pin serial port Reading & processing of HDLC data from 25 pin serial port Reading & processing of HDLC data from 25 pin serial port
Reading & processing of HDLC data from 25 pin serial port Reading & processing of HDLC data from 25 pin serial port
Reading & processing of HDLC data from 25 pin serial port
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Old 12-22-2010, 08:48 PM
chandrakari chandrakari is offline
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Default Reading & processing of HDLC data from 25 pin serial port


i am having some knowledge serial port communications using Ms Comm control. when i am trying to do the same thing for HDLC protocol data, i am getting junk. is this is different from normal serial port communication? . any algorithm is to be implemented? some help please.

thank you
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Old 12-22-2010, 10:01 PM
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dilettanteReading & processing of HDLC data from 25 pin serial port dilettante is offline
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I believe HDLC (and the related SDLC) is normally used over synchronous serial connections, something that the MSComm control doesn't support (or support well) and many COMx: ports don't support.

HDLC itself is a protocol, like the Ethernet protocol (not to be confused with the Ethernet media interfaces themselves). A variation of HDLC is used for PPP in Windows Dialup-networking or RAS, but I don't think it can be used as a general purpose HDLC solution.

You're not likely to get desireable operation at high speeds by implementing HDLC in VB6, and in any case as I said I don't think MSComm will cut it anyway. As far as I know most successful uses of HDLC/SDLC on a PC involve a specialized add-in card, and these probably have a small processor and logic on them to process the HDLC protocol. These were often used with PC software to provide a sort of IBM 3270 Terminal Emulator that could be connected to HDLC (SNA) terminal networks.

If you really need to do this, I'd look for HDLC add-in cards that offer an SDK.
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Old 01-08-2011, 02:15 PM
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mkarasReading & processing of HDLC data from 25 pin serial port mkaras is offline
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Get your self a synchronous protocol adapter that attaches to a USB port. Here are some to consider...

http://www.systexcomm.com/en/products/usinlink.asp

http://www.farsite.com/synchronous_u..._Windows.shtml

http://www.advancedrelay.com/ci/products/pxsu

mkaras
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Reading & processing of HDLC data from 25 pin serial port
Reading & processing of HDLC data from 25 pin serial port
Reading & processing of HDLC data from 25 pin serial port Reading & processing of HDLC data from 25 pin serial port
Reading & processing of HDLC data from 25 pin serial port
Reading & processing of HDLC data from 25 pin serial port
Reading & processing of HDLC data from 25 pin serial port Reading & processing of HDLC data from 25 pin serial port Reading & processing of HDLC data from 25 pin serial port Reading & processing of HDLC data from 25 pin serial port Reading & processing of HDLC data from 25 pin serial port Reading & processing of HDLC data from 25 pin serial port Reading & processing of HDLC data from 25 pin serial port
Reading & processing of HDLC data from 25 pin serial port
Reading & processing of HDLC data from 25 pin serial port
 
Reading & processing of HDLC data from 25 pin serial port
Reading & processing of HDLC data from 25 pin serial port
 
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