Re: [stella] button questions

Subject: Re: [stella] button questions
From: Ruffin Bailey <rufbo1@xxxxxxxxxxx>
Date: Wed, 17 Jul 2002 09:43:02 -0400
On Tuesday, July 16, 2002, at 10:37 PM, Chris Wilkson wrote:
This is a good test.  But see above.  Try replacing BNE with BMI and
it should work.  There's also the possibility that you aren't disabling
the latches.  I'm fuzzy on those details...I'd have to look them up.
But I'm sure someone else can help.

From what Eckhard told me just a few days/weeks ago, you'd be best served by (un)latching VBLANK (whatever hitting D6 is) every frame if you have a simple kernel. It would appear that your BNE was what what creating what you described as...
it doesn't seem to matter if I
	LDA #%01000000
instead of just letting it be #0
So I guess I don't get the implication of the
whole latch thing...

Once you've substituted BMI, try putting 1 back into D6 of VBLANK just like you'd done before. I bet that works. I think more recent versions of my code have an okay joystick read routine, including the buttons.

Eckhard further explained that the latch bit can get more complicated if your kernel only checks for button presses every, say, third screen draw (as I understood him). If you throw down the latch, you can preserve the button press until you deal with it.

But I'm not doing anything that fancy, and am not *quite* sure how that's helpful yet. Insert "young grasshopper" reference (meaning me in this case).

Hope that helps,

Ruffin Bailey

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