#: 3385 S7/Telecommunications
    09-May-90  19:21:12
Sb: #3330-#RE 3293
Fm: Bruce Isted (UG VP) 76625,2273
To: LUTE MULLENIX 70721,2230 (X)

~ Lute,
  The problem you describe with transmit locking up, and then the program
locking up when you try to quit, sounds like your modem isn't asserting DSR. In
order for ACIAPAK to work properly with a modem, the modem must always assert
DSR, or you must tie DSR on the RS-232 Pak so that it is always enabled.
  Usually people only have trouble with the 6551 ACIA (thats the one in the
RS-232 Pak and clones) because they don't see any characters until the DCD line
is enabled... but the DSR problem is even worse when you run into it.
  The way the ACIAPAK driver works, if DSR is or isn't enabled when the serial
port, its OK... and transmit data works.  Then, when the modem raises DSR when
you first CONNECT, everything still works OK because DSR is valid and transmit
is enabled.  When the modem disconnects, if the DSR drops *THATS* when the
problem occurs.  The ACIAPAK driver sees that DSR is no longer valid, so it
disables transmit data... which means you can no longer communicate with the
modem to force DSR on (if your modem supports such a command), or to do
anything else.  Finally, when you quit the program it hangs up, because there's
transmit data to be sent, and transmit is disabled, so the buffer can't be
flushed.
  The best bet is to look in your modem manual for a DIP switch setting that'll
always enable DSR, or to look for a command that'll do the same job.
  Bruce

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