SLROM pcb w/ 27c1000 eproms pinout help!

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SLROM pcb w/ 27c1000 eproms pinout help!
by nintendo2600 on 2009-04-06 (#45277)
Hey,

When making an eprom cart using a SLROM board the eprom conversion sheet doesn't mention 27c1000 chips. I assume all would be the same aside from pin 24 not being needed to be bent up nor pin 2 needing to go under 24 on the pcb for either chr or pgm do to the pinout of the 27c1000 being closer to that of what nintendo used on their production roms correct? AKA anyone got a shematic to use 27c1000's for the SLROM board type please?

Shawn

by nintendo2600 on 2009-04-07 (#45307)
no love? :oops:

by AWal on 2009-04-07 (#45308)
Flash: Tie all those to Vcc
EEPROM: Tie 31s to GND (This solves an accidental 5v programming glitch on some chips), Tie rest to Vcc

You said it's a 27C1001, so go with EEPROM.

If they are left floating, the lines tend to ping-pong on CMOS devices, causing inconsistencies in data, hence why they are all tied.

Also, when burning, make sure to repeat data if necessary, just in case the program invokes any extra bank data.