Hit an amusing one today; an aging 12C509 still in production, with
code from 2001, which reads GP3 to set reporting units, which had GP3
floating by my soldering error, had begun reading a zero occasionally;
about one in a million reads.

So I added the missing strap.  Let's see how it goes.

Hmm.  But pull-ups are enabled.  Either pull-ups are damaged, or the
circuit was picking up stray RF.  The GP3 trace is about 2cm long.

Relevant code selective copy and paste;

	;; set option register to enable pull-ups and enable GP2
	MOVLW	B'10011111'	; NOT_GPPU, T0CS
	OPTION

....

	MOVLW	B'00111011'
	MOVWT

....

	;; test for fahrenheit mode, gp3 low
	;; (if left open, it is pulled up to high)
	BTFSS	GPIO,3

....

--=20
James Cameron
http://quozl.netrek.org/
--=20
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