MPLAB SIM and Alternate pin function!?

[Aedan]

I'm throwing this out to see if anyone else can make sense of this...

Some background: I'm "playing" around with a PIC 12F615 microcontroller. Ultimately, if I can make it do what I want it to do, it'll control a remote control toy. I've written a fair bit of code that works in a simulator. Except for one small part. As the "user interface" of the device is actually an IR transmitter, I need to be able to receive IR pulses. The code I'm using is using one of the timers to time how long a pulse is, in order to determine if it's a zero or a one.

Due to the way the pins are set up, I need to use an alternate pin function for timer 1 gate (T1G). However, when I try this in the simulator (MPLAB SIM), it doesn't appear to work how I expect it to work. A small sample of code is below:

; Alt !T1G Testing
;
	#include <P12F615.INC>
	__CONFIG h'3CD4'
	org 0
Start:
; IO Port Setup
; T1G is GPIO4
	BANKSEL	ANSEL
	CLRF	ANSEL		; Digital I/O, ADC off.

; Timer1 gate setup
	; !T1G is normally GP4
	; Select alt !T1G - GP3 input
	BANKSEL	APFCON
	BSF		APFCON,T1GSEL

	BANKSEL	T1CON
	MOVLW	b'11000001'	; Gate active high and enabled, timer on
	MOVWF	T1CON		; Let's go!


	GOTO $ 				; And go...
END

Am I just stupid, or is something else going on here? All the software needed can be downloaded for free from this page: MPLAB Integrated Development Environment.

[Gizmo]

Perhaps this is one of those corner-cases where the hardware behaves slightly different than the emulator?

Too bad they chose to write their own IDE (that is windows-only) rather than a plugin to Eclipse.

[Aedan]

I'm presuming that it must be bug in the SIM. Too bad, as I was hoping to test out my IR reception code to ensure it works as designed! I didn't want to have build a test rig to check things out, but I guess I will have to do so!

[Aedan]

The Linux simulators haven't yet caught up with the devices I'm using, but MPLab does run fairly well under wine. As far as MPLAB goes, the majority of their software can be called from the command line, but not the simulator.