So I was fairly sure this was my own beat up NES causing the problem, plus I thought I'd resolved it (magically), but enough signs point to that not being the case that I'm compelled to ask about it.
I'm using CHR-RAM. At the start of the game, I turn the drawing off (and in NMI at the end, even have a case to check whether I should turn drawing on or not - thought this fixed the problem, but did not). The first thing that happens after the reset is a load of all the CHR-RAM, loading the first nametable, and loading some init variables.
The first time the NES fires up, the tiles to be loaded appear incorrectly...everything is in the right places and functionality all works, and even the palettes are correct, but it's just a jumble of visual data. Upon pressing Reset (or even full power off then quick power on) everything is loaded perfectly fine.
I've heard a few folks postulate what could be causing this, but haven't yet found a solution. Any thoughts?
** Note, this also only happens on hardware, and on both an actual NES and a clone system, if that helps**
Thanks!
I'm using CHR-RAM. At the start of the game, I turn the drawing off (and in NMI at the end, even have a case to check whether I should turn drawing on or not - thought this fixed the problem, but did not). The first thing that happens after the reset is a load of all the CHR-RAM, loading the first nametable, and loading some init variables.
The first time the NES fires up, the tiles to be loaded appear incorrectly...everything is in the right places and functionality all works, and even the palettes are correct, but it's just a jumble of visual data. Upon pressing Reset (or even full power off then quick power on) everything is loaded perfectly fine.
I've heard a few folks postulate what could be causing this, but haven't yet found a solution. Any thoughts?
** Note, this also only happens on hardware, and on both an actual NES and a clone system, if that helps**
Thanks!