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#17 Modem Control

open
nobody
None
5
2013-01-13
2005-11-22
Norbert
No

For half duplex communication with FSK modem over
leased line, I need modem control functions as follows:

1. similar to rs485mode, rts line is set to true before
transmission can start. The cts line is monitored -
packet is sent out only if cts becomes active after
programmable delay (0 ... x ms). If cts remains
inactive, packet is lost.

2. same function as above, but transmission starts
after programmable delay without monitoring cts.

In both cases, rts is deactivatetd after packet is sent
out or discarded.

Discussion

  • Robert C

    Robert C - 2006-09-25

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    Why can't you do this in code? Whats stopping you?

     
  • msn

    msn - 2007-04-12

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    good

     
  • Norbert

    Norbert - 2007-04-12

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    due to different reason this feature was less important.
    However:
    In a multi-threaded application serving differenet leased lines with RTUs in party line configuration it doesn't seem to be a good idea for an application to wait for handshake signals becoming active/passive etc. A better approach would be to have a communication thread which handles all these things automatically when the application wants to send a data packet. TpApro does this in the case You setup the port component for RS485 mode but this is not sufficient...

     

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