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HI
I tried to make a Zelda with a 1a3b-20 board (loron), this cart has a 74ls139, a 64k sram and space for one rom chip. I am using two flash rom of 4Mbit.
to make the decording I use a 74ls00 (nand), taking pin 7 from 74ls139 (it was connected to oe from rom chip) and connection this pin in a gate with 5v, I took this output and connected to two gates, first with A19 and second with noA19, each output to each oe from flash chip.
the game run ok at the beginning, but, the problem is when I have to save a name at the beginning, the letter are wrong, they are repeat like this: a b a b e f e f i j i j m n m n...
and doesn't save.
what can be the problem?
thanks

Does that mean SRAM address bit 1 isn't connected properly?

I am really thankfull, the bubble was broken (sure that I broke it desoldering the old rom chip) and didn't connect both traces (cartridge connector and sram pin) so pin D1 was floating, but now is working perfect.
thanks

For future reference, you should be selecting your ROMs using /CE, not /OE. Not only will it save power but you won't have timing issues in other more strict applications.