![]() So I designed Atmega8 based reader just for sake of this single chip. And I was worried that the flux residues from desoldered chip could block electric connection on some pins. TL866 programmer does not support this memory directly, so I would need to make my own adapter, using TSOP56 socket. My next goal was to dump the ROM content. * there are two 0R jumpers on blob pins to GND which suggest they can switch the crystal between 26MHz and 21MHz and video mode between PAL/NTSC (just guessing, I didn't test that). * mysterious button underneath is just second on-off switch, which cuts power to everything except the power LED diode * its quite hard to say if the RAM is used as additional PRG-RAM or CHR-RAM, (or maybe both, depending on the game?) ![]() * both ROM & RAM chip's address & data lines are shared (except RAM's A0, which is controlled by separate signal) * despite that A23 is NC inside ROM, it is still wired to blob, so theoretically 32MB ROM can be placed instead, * 5V are lowered with two diodes in series to +3.6V, which powers ROM and blob * there is SOT89 (CE8301A?, marking E5) boost switching power supply which produces +5V, used to power RAM only Reverse engineered schematic reveals that: ![]() First look at the PCB shows TSOP56 ROM (PRG-ROM?), RAM (CHR-RAM?), one blob chip (NES on chip + mapper), some discrete logic (inductor - might be switching power supply, video amplifier).Īfter selecting game from menu, it starts immediately, which means that the PRG and CHR data, stored in one memory are immdiatelly accessed by both CPU and PPU (in contrary to the big XXX-in-1 coolboy cartridges, where CHR data needs time to be copied from PRG to CHR-RAM chip). My first impression was quite good - I inserted 2 almost empty AAA batteries and it ran fine, so probably needs very little current.
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