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From: "Mr. TR Nguyen" <xxnguyen@utacnvx.uta.edu>
Message-Id: <199506290242.VAA22022@utacnvx.uta.edu>
Subject: APC Backups 400 && ups daemon
To: freebsd-questions@FreeBSD.ORG (freebsd-questions)
Date: Wed, 28 Jun 95 21:42:48 CDT
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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)

Here's what the simplistic logic looks like:
	open() "/dev/tty2"  # comm 3
	LOOP FOREVER:
		read() a single byte
		check to see if bit #4 has been set
			.....
	END LOOP


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

Thankx so much,
TR Nguyen