cschell Posted December 2, 2002 Share Posted December 2, 2002 Ok, some questions for the 5200 gurus on 5200 cartridge hardware. The faq pinouts show it has two "enable" lines, 40-7F and 80-BF. As I don't have a 5200 PCB to comparison, I figured I ask about these. Are they active low? Or high? Assuming they're active low, that means I would enable the EPROM when either went low (32K game of course.) Would I then connect the 40-7F line to A15 of the eprom? That would mean that when 40-7F enable went low, the eprom would be active and the lower half of its contents would be selected. The next question after I get this sorted out will be: What's the format for BBSB bankswitching? Thanks, Chad Quote Link to comment Share on other sites More sharing options...
CPUWIZ Posted December 2, 2002 Share Posted December 2, 2002 The CE lines are active low, like a standard EPROM. As to BBSB, I just reverse engineered how the bankswitching works and I am not ready to share my finds. Quote Link to comment Share on other sites More sharing options...
cschell Posted December 2, 2002 Author Share Posted December 2, 2002 As to BBSB, I just reverse engineered how the bankswitching works and I am not ready to share my finds. Do you have exciting plans for this knowledge, or do you just like being stubborn? Chad Quote Link to comment Share on other sites More sharing options...
CPUWIZ Posted December 2, 2002 Share Posted December 2, 2002 Both. Why are you asking about the BBSB bankswitching anyway ? Quote Link to comment Share on other sites More sharing options...
cschell Posted December 2, 2002 Author Share Posted December 2, 2002 Because I'm mulling over 5200 ramcart stuff, and I don't own a BBSB to examine. Quote Link to comment Share on other sites More sharing options...
+Mitch Posted December 2, 2002 Share Posted December 2, 2002 Chad, check here for the 5200 EPROM mod. If you haven't already seen it. I seem to remember someone (Dan B?) posting the bankswitching info on 5200 Bounty Bob a while back. I can't remember if it was here or on Usenet. Mitch http://atari7800.atari.org Quote Link to comment Share on other sites More sharing options...
cschell Posted December 2, 2002 Author Share Posted December 2, 2002 This looks like it will be a very short lived mulling anyway. Again Atari failed to bring either the clock or r/w line to the cartridge port. This means that once again, it would be a pain to get modern high speed parts to successfully perform RAM writes if the cart were to load games "in system." As I'm not 5200 fan I just can't motivate myself to deal with that hassle for this platform. The other option would be just to load games from the PC into NVRAM and stuff the cart into the 5200 preloaded. Of course that's just an eprom emulator, not very exciting or unique. Also hard to justify the cost of a PLD or MCU or both on board to accomplish something other than parallel port loading and BBSB support. Chad Quote Link to comment Share on other sites More sharing options...
+Mitch Posted December 2, 2002 Share Posted December 2, 2002 I suppose there's always the Colecovision... Mitch http://atari7800.atari.org Quote Link to comment Share on other sites More sharing options...
cschell Posted December 2, 2002 Author Share Posted December 2, 2002 The Colecovision has similar problems actually. Otherwise I think you could use a gameboy flash cart on the Colecovision with an adapter. Chad Quote Link to comment Share on other sites More sharing options...
+Mitch Posted December 2, 2002 Share Posted December 2, 2002 That's true. I don't think it has any bankswitched games either. So it would basically just need an EPROM emulator. Quote Link to comment Share on other sites More sharing options...
cschell Posted December 2, 2002 Author Share Posted December 2, 2002 Yes, that's the reason that I've turned down so many people when they've suggested that I make a Colecovision ram cart. Quote Link to comment Share on other sites More sharing options...
DanBoris Posted December 2, 2002 Share Posted December 2, 2002 You could get tricky and pull the R/W and clock signals off the expansion port. You would just have to have a second cable coming out of the cartridge to connect to the port. Dan Quote Link to comment Share on other sites More sharing options...
Paul Slocum Posted December 2, 2002 Share Posted December 2, 2002 Both. But I'm not. Bounty Bob Bankswitching: - Four 4 KB banks (A,B,C,D) are mapped into $4000-$4FFF. An access to $4FF6 selects bank A, $4FF7 - bank B, $4FF8 - bank C, $4FF9 - bank D. - Four 4 KB banks (E,F,G,H) are mapped into $5000-$5FFF. An access to $5FF6 selects bank E, $5FF7 - bank F, $5FF8 - bank G, $5FF9 - bank H. - The remaining 8 KB is mapped to upper 16 KB of cartridge address space in Atari 5200. That is, $8000-$9FFF and $A000-$BFFF contain same data. Quote Link to comment Share on other sites More sharing options...
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