An SNES DIP 42 Lorom/hirom with save feature ( 256kb sram max in lorom , 64kb max in hirom )

latest revision 1.3b of pcb support 256kb save in hirom

you can set the sram size to 256kb (32ko ) , 64lb ( 8ko ) or 16kb (2ko) by bridge the pads like indicated on the pcb

2mo maximal capacity , 4mo 27c322 IS NOT SUPPORTED because we cant force it to work in 8bit

if you want 4mb check for my snes flashcard

you can use dip42 eprom type 27c160 (2mo ) or 27c800 ( 1mo )

they are easy to find and cheap

need bridge pads for lorom or hirom depend of the game used

parts needed :

1x UV Eprom 27c800/160

1x sram LY62256SL-70LLI or another with same pinout and low power standby

1x 74hc139 DP 16

2x 1n5817 diodes

1x cr2032 battery , you can use a socket if you want

1x bc847 transitor

1x 22uf capacitor SMD 1206

5x 100nf capacitors SMD 1206

1x 100uf capacitor ( optionnal ) SMD1206 , 47uf or 22uf fines too

1x pic 12f629 or 12f675 in DIP8 programmed with supercic HEX

3x 10k resistor SMD1206

1x 1k resistor SMD1206

the 100uf capacitor is optionnal , its for sram for let you the time to change the battery without loose your save , 100uf keep the save few minutes

all other part are needed

you have pad for configure the sram size for make it according to your game ( 256kb , 64kb or 8kb )

pcb work ok i tested it with zelda (lorom ) and secret of mana ( hirom )

need order pcb in ENIG ( minimum ) and 1.2mm thickness

NOT 1.6mm VERY IMPORTANT