ASYNC (1) ASYNC BIOS REPLACEMENT ASYNC (1)


NAME
NAME

ASYNC.COM

SYNOPSIS
SYNOPSIS

async com
async.com [0|1]

DESCRIPTION
DESCRIPTION

async com
async.com is a terminate-and-stay resident program that
replaces the IBM-PC ROM-BIOS asynchronous communications
services with a servicable interrupt-driven communications
driver.

async 0 async 1
To invoke it, type async 0 or async 1 and it takes over the
communications port. Since PC-DOS uses the rom bios INT 14H
COM1 COM2 AUX
service for all I/O on the COM1, COM2 and AUX devices, this
program becomes the driver for those devices.

async com
Once async.com becomes resident, all input and output to the
com-port devices is run through an interrupt driven hardware
driver, that is buffered both on input and output.

This is especially useful in conjunction with the PC-DOS
CTTY
CTTY command, which redirects the console device. The
standard ROM-BIOS driver is polled, and has a tendency to
lose characters at high input and output rates.

CAVEATS
CAVEATS

async com CTTY
If you use async.com in conjunction with CTTY, keep in mind
that the CON device is still the PC system console. This
COPY CON FILE DAT
means that if you try to do a COPY CON FILE.DAT, the system
is hung until someone at the physical console types a
control-Z.

BASICA
BASICA is, of course, a no-no, as it does its own
communications device handling.

async com
If you want to use both async ports with async.com, invoke
it twice, once for port 0 (com1) and once for port 1
(com2). I am not sure what happens if you stack more than
async com
one copy of async.com for a given port, except that I/O will
probably slow down, and more memory will be used up.
async com
async.com doesn't check to make sure that it hasn't already
been invoked.

The best way to use async.com for going 'outside' from a BBS
is to use the PD utilities MARK and RELEASE, included in
this package. Also included is the TSR.DOC file that
MARK async com
describes their use. If you MARK before invoking async.com,
RELEASE
and then RELEASE when you're ready to go back to work, you
async com
don't leave async.com dangling in memory. An example is
included below.





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ASYNC (1) ASYNC BIOS REPLACEMENT ASYNC (1)


EXAMPLES
EXAMPLES

The following is a batch file for invoking a dos shell from
a BBS. You may note that a copy of each command is echoed
CON CTTY COM1
to the CON device, which is not redirected by CTTY COM1.

ECHO OFF
ECHO FMARK \TMP\ASYNC >CON
FMARK \TMP\ASYNC
ASYNC 0
ECHO MODE COM1:96,n,8,1 >CON
MODE COM1:96,n,8,1
ECHO CTTY COM1 >CON
CTTY COM1
ECHO PC-SHELL >CON
COMMAND
ECHO CTTY CON >CON
CTTY CON
ECHO RELEASE \TMP\ASYNC >CON
RELEASE \TMP\ASYNC

async com
To use async.com with this batch file (assuming it's called
outside.bat) :

ASYNC 0 OUTSIDE


FILES
FILES

Filename Length Method Size Ratio Date Time
-------- ------ ------ ------ ----- ---- ----
ASYNC.C 954 Crunched 661 31% 10-10-86 14:00:10
ASYNC.COM 4106 Crunched 3105 25% 10-10-86 14:05:26
ASYNC.DOC 4422 Crunched 1800 60% 10-10-86 14:33:44
FMARK.COM 640 Crunched 407 37% 07-20-86 13:33:40
FORKP.C 2477 Crunched 1419 43% 09-25-86 09:19:10
HANDLER.ASM 3583 Crunched 1831 49% 10-10-86 09:55:54
INTCOMM.C 3335 Crunched 1746 48% 10-10-86 08:37:16
MAKEFILE 246 Crunched 184 26% 10-10-86 14:33:24
MARK.COM 1408 Packed 174 88% 07-20-86 13:33:02
MINT.C 3001 Crunched 1589 48% 10-10-86 13:09:06
RELEASE.COM 16647 Squeezed 15914 5% 07-20-86 13:32:36
STKSIZ.C 1011 Crunched 697 32% 10-09-86 13:41:32
TEST.BAT 247 Crunched 162 35% 10-10-86 14:19:12
TSR.DOC 14675 Crunched 7166 52% 09-07-86 13:01:30
_CROOT.C 2068 Crunched 1269 39% 09-24-86 16:00:30

NOTES
NOTES

async com
async.com was prepared using AZTEC C86. Debugging was done
with ATRON's software probe software.

This program was written by:

Kent Williams 722 Rundell Iowa City, IA 52240 (319)
338-6053

The mark and release utilities were extracted from


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ASYNC (1) ASYNC BIOS REPLACEMENT ASYNC (1)


TSRCOM.ARC - which is floating around in FIDO-land.
They are included here as a service, without
permission.

RETURN VALUE
RETURN VALUE

None





















































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