Subject: Re: [stella] 3F question From: "Eckhard Stolberg" <Eckhard_Stolberg@xxxxxx> Date: Sun, 10 Jul 2005 15:33:49 -0400 |
> I've added code to 3F that makes it do both... but I just wanted to > ask the experts and make sure I'm doing the right thing: A write to any > of the standard TIA addresses on real 3F hardware will affect both the > TIA and the bankswitching. Is this correct, and are there any special > cases I should know about? Yes, this is how the standard implementation of 3F bankswitching works. There are no special cases regarding the TIA, but if you want to go for 100% acuracy, you should also note that the bank will only be changed, if the next address accessed after the write to $003F is in the ROM area. So a STA $3F will work when executed from ROM but not from RIOT RAM, because the next address on the bus will be the opcode fetch for the instruction after the STA $3F. Ciao, Eckhard Stolberg Archives (includes files) at http://www.biglist.com/lists/stella/archives/ Unsub & more at http://stella.biglist.com
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