nesdev.org

nintendo2600 wrote:

marvelus10 wrote:It works I have tried it, the only difference I could find in using the new RAM chip is that it runs faster at 150ns. I cant tell you why or how I don't know enough about it, but I assure you it works.

Did you also try it with the stock SRAM before swaping it out for the new SRAM?

Yes I did it will get the opening screen with accelerated sound then crash when you go to the level select screen.

Anyone got it working !? Something weird is that the sony sram is 150ns and many nes cart have faster stock sram !! ex: 80ns

marvelus10 confirmed it working, but I am more interested in why it works.

Somebody want to look at the changes in the ROM and maybe try to explain it, I'm curious.

If someone managed to "fix" the scanline counter in a way that sprites from both pattern tables can be used, I'm really interested in hearing about it.

At this point I've done some small work into getting this running. On my TKROM board I've removed a SONY CXK5864PS-12LL and replaced it with an ALLIANCE AS7C256-20PC.

Originally I had desynced/partly accelerated sound (I think the triangle channel is the one that is running too fast), crashing on power-on otherwise (black screen).

With the new chip, the title screen appears to run fine (my EEPROM that I was using for CHR broke, so I'm SOL for confirmation there), but when I press start (twice) to go to the "warp screen," I receive the music box music instead, and when the stars put mario in place, the cartridge locks up as if I had bumped the nintendo.

I've patched all the PPU bank select writes to not mix (in the old topic I dumped an IPS patch), and this hasn't helped so far.

Anyone know a place to buy these sony sram chip in smal quantity !? ex: 1 or 2

flagoss wrote:Anyone know a place to buy these sony sram chip in smal quantity !? ex: 1 or 2

I suggest calling MCM Electronics on this one. They probably have them.

I may have some laying around too, and if I find any, I'll let you know.

-Xious

So, did you all get this going or what? =)

hey any update anyone ?? Have you ever got it to works ??

Good information here! I'm also curious to see if anyone got it working properly.

As far as installing the new SRAM chip, I have a socketed TSROM cartridge with a cutout in the front so I can pop EPROMs in and out without disassembling it. So far it's been working flawlessly for about a year now. This is the cartridge that I had planned on trying Mario Adventure on, until I came across people having issues. Does anybody know if replacing the SRAM chip with the faster version will negatively affect other games that already work fine with the old SRAM chip? (ie. dpad hero, dpad hero 2, smb2 japan, etc?)

I'd be curious to know if anyone understood why this fixed it. I'm not sure if the speed exactly matters, as the SRAM usage is basically the same for every game (other than when mappers offer write-protect function). I've used 10ns SRAMs on a cart before and would expect it to work the same as one that is a slow as possible, weird. But I could be wrong, often am, heheh.