I tried to make the cartmodd two TSOP with a cartridge of NHL 95 (Hirom, Mad-1 + SRAM + Simple Maskrom)
I used the game Chrono Trigger News Translation (48MB) "Chrono Compendium patch"
It is always interesting to assemble it in order to understand the wiring.
It is a fairly simple installation, three wires are welded to the MAD-1
"TSOP 1"
Pin 22 (OE) to MAD-1 pin 01
"TSOP 2"
Pin 22 (OE) to MAD-1 pin 16
"MAD-1"
Raise pin 13 and solder to TSOP pin 35 (A22)
As rightly said electrochip, the game works but the backup does not work.
It remains for me to try it out with a cartridge containing the chip on the PCB 74LS139, I have no cartridge equipped 74ls139 right now, I would do this test a little later.
Some pictures:



It's okay ?

Edit:
Bingo !!!!!its backup




I found one in my house one 74LS139 and I finally could do the test.
Thank you all for your explanation