gnupic: Remarks to gpsim of 05/12/2006
Subject:
Remarks to gpsim of 05/12/2006
From:
Tobias Schlottke ####@####.####
Date:
19 May 2006 13:01:24 +0100
Message-Id: <Pine.LNX.4.64.0605191400560.29203@ws-toby.Netzwert.AG>
Hi all,
I downloaded the top svn version at 05/12/2006 and
tested with the following small program:
=========================8<======================
processor 16f84
include "p16f84.inc"
org 0
bsf STATUS, RP0
movlw 1
movwf TRISA
bcf STATUS, RP0
bsf PORTA,0
nop
finito:
btfsc PORTA,0
movlw 53
goto finito
end
=========================8<======================
It sets bit 0 of PortA as input,
sets bit 0 of PortA to 1 and
checks the state of bit 0.
Right now its evaluated to 1, so movlw 53 is executed.
That is not what I've expected. By default all inputs
are read as 0, so even if I try to overwrite the value
it should not change.
But:
====
If I connect a stimulus to the port gpsim behaves as
expected, the bit is sampled as 0. Unfortunally the
change of the state of the port is not visible in the
breadboard window. So gpsim behaves like the real
world: undefined pins are evil....
Best regards,
Toby
