Tickled_Pink Posted July 25, 2004 Share Posted July 25, 2004 Took a quick look at the 5200 memory map and specs a couple of nights ago and I have one question in relation to converting A8 software to the 5200. How does the 5200 access its ROM space? By that, I mean which area of ROM does it access first when booting up? The reason I ask this is that the A8 has two 8K ROM areas, with the upper 8K being loaded first. The 5200 has a 32K ROM area. I'm just wondering how easy it is to convert from one to the other. Changing the addresses for the custom chips is probably easy enough, the joysticks maybe a touch trickier but what about code relocation? Hence my question. Does the 5200 load up ROM at the same memory location as the A8? Quote Link to comment Share on other sites More sharing options...
CPUWIZ Posted July 25, 2004 Share Posted July 25, 2004 The very first thing the 5200 does is look at the reset vector, which is at $BFFE, it then jumps to that address. Location $BFFD determines if the 5200 should display the splash screen or not, $FF at that memory location means don't display it. Quote Link to comment Share on other sites More sharing options...
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