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Disabling serial terminal flow control?

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The Question is:

 We have Alpha server 800/500 with two COM-ports:
 COM1 for Remote Management Console;
 COM2 for usual implementation.
We want to use the both COM-ports for data flow Input/Output in a transparent
 mode (without any
filtering in both directions) at a boad rate of
9600, no parity check, 8 bit frame with 1 stop bit.
 Operating system OpenVMS V7.1-1H2, console firmware V5/3-101, palcode 1/20-3.
 Unfortunately, as we found out, COM1 acts the way different from that of COM2:
 it doesn't pass
codes Ctrl/S and Ctrl/Q (13 and 11 hexadecimal)
although the environment variable COM1_FLOW_CONTROLE is set to NONE just as for
COM2. At the OpenVMS level the flow controle is forbidden by appropriate SET
 TERM command both
for COM1 and COM2:
$ set term/perm/noecho/pasthr/notyp/NOTTSYNC TTA0:   !COM1
$ set term/perm/noecho/pasthr/notyp/NOTTSYNC
TTB0:   !COM2
 Our question: is there any way to make COM1 port act the same way COM2 does
 (to transmit all codes transparently in both directions)?
Perhaps some firmware upgrade or, may be there are some undocumented console
 commands to cope with this problem? We don't need to use a Remote Management
 Console mode.
Thank you,
Risover L.

The Answer is :

  Please get off V7.1-1H2, moving to (at least) V7.1-2, and also
  move to the current SRM firmware.
  Please ensure that the console is set to graphics, not to serial.
  (See the environment variable named "console" for the setting.)
  Disabling flow control is rather difficult, as most hardware does
  not support hardware flow control and thus any data over-runs can
  produce some rather interesting application-level problems.
  Please look seriously at using a terminal server or at a PCI-based
  terminal controller, as the existing COM lines are intended for
  use with low-volume output (terminals, low-speed printers) and not
  for high-speed or high-volume communications.
  Please contact the Compaq Customer Support Center, as this will
  likely require further investigation.

answer written or last revised on ( 14-SEP-2000 )

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