Hi. I managed to get the board to boot the neodiag bios.
Now i'm having the 3 following problems (among others):
1. backup sram is missing. In an online picture i can see that the sram is LH52B256N-70LL. Can i replace it with HSRM20256LM. I xould't find a datasheet, but on console5 it says it's a pseudo static sram with refrash on oe. If not, what's the slowest sram i can use?
2. CR4 and CR6 are dead. here's the schematic: https://wiki.neogeodev.org/index.php?title=CRE401
a) what value should I use for the caps? 100nf is ok?
b) About the 300R. I measured a working part and on my pcb is about 200R. Can I use 180R or 360R?
3. Use the retail bios and no cart i get this error: COLOR RAM BANK0 ERROR. address 00400000 write 0000 read 1F00
Bank 0 is RAM7 or RAM8? I hope it's not the neo-buf at GA4.
Now i'm having the 3 following problems (among others):
1. backup sram is missing. In an online picture i can see that the sram is LH52B256N-70LL. Can i replace it with HSRM20256LM. I xould't find a datasheet, but on console5 it says it's a pseudo static sram with refrash on oe. If not, what's the slowest sram i can use?
2. CR4 and CR6 are dead. here's the schematic: https://wiki.neogeodev.org/index.php?title=CRE401
a) what value should I use for the caps? 100nf is ok?
b) About the 300R. I measured a working part and on my pcb is about 200R. Can I use 180R or 360R?
3. Use the retail bios and no cart i get this error: COLOR RAM BANK0 ERROR. address 00400000 write 0000 read 1F00
Bank 0 is RAM7 or RAM8? I hope it's not the neo-buf at GA4.
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