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From: Michael Smith <msmith@atrad.adelaide.edu.au>
Message-Id: <199506290744.RAA22262@genesis.atrad.adelaide.edu.au>
Subject: Re: APC Backups 400 && ups daemon
To: xxnguyen@utacnvx.uta.edu (Mr. TR Nguyen)
Date: Thu, 29 Jun 1995 17:14:56 +0930 (CST)
Cc: freebsd-questions@FreeBSD.ORG
In-Reply-To: <199506290242.VAA22022@utacnvx.uta.edu> from "Mr. TR Nguyen" at Jun 28, 95 09:42:48 pm
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Mr. TR Nguyen stands accused of saying:
> I think hackers would be a more appropriate forum, but it's kind
> of swamped for the time being. Anyways, I have an A.P.C. Back-UPS 400
> with a serial connection to my FreeBSD 2.0.5R's comm port 3.
> 
> I've unsuccessfully tried to write a simple program to read a single
> byte from this port (/dev/tty02) and check whether or not the "POWER-FAIL"
> bit has been raised (pin #4, according to the Owner's Manual)

Urk.  You're confusing pin 4 (CTS) with bit #4 in a serial data stream.

> Anyone with examples/tips to share with this stumped-abuser?

Yup; try this :

int	fd, status;

  fd = open("/dev/tty2",O_RDONLY);

...

  for(;;)
  {
    status = ioctl(fd, TIOCMGET, NULL);
    if (status & TIOCM_CTS)
      power_has_failed()
    sleep(60);
  }

Haven't tested it, but it ought to work 8)

Make sure you don't have a getty on the port at the same time.

> TR Nguyen

-- 
]] Mike Smith, Software Engineer        msmith@atrad.adelaide.edu.au    [[
]] Genesis Software                     genesis@atrad.adelaide.edu.au   [[
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