Unknown Amstar Elec Etched in copper on top of board AMSTAR ELEC ASSY 1061-3700/ (c) SER NO Etched in copper on daughter card PROM 1 PROM 2 1061 3750 COMP SIDE .e8 tms2764 on a daughter card at E8 .e5 2708 .g1 6301 read as 82s129 .j2 6301 read as 82s129 handwritten sticker couldn't read .h2 6301 read as 82s129 handwritten sticker couldn't read .g2 6301 read as 82s129 handwritten sticker couldn't read .f2 7611 read as 82s129 handwritten sticker couldn't read - programmer said chip was bad .d2 stickered 1-140 empty 14 pin socket at j1 empty 16 pin socket at g11 empty 24 pin socket at d5, b6, b7, b8, c7, c8, e8 roms? .b4 24 pin Signetics 7847E C27139M 4502 .b5 24 pin Signetics 7848E C27138M 4501 Traced the pins... Most pins connected to the 2708 so that was used for signal names A7 VCC A8 D0 A9 D1 Pin 4 of a 74157 D2 A0 D3 A1 D4 A2 D5 A3 D6 A4 Pin 18 of a 74374 A5 Pin 4 of a 7400 for B5 and Pin 13 of a 7400 for B4 A6 GND GND Pin 5 of a 4700 Mame .280 C:\Mikes_old\roms>c:\games\mame\mame -romident c:\mikes_old\roms\ae\roms Identifying c:\mikes_old\roms\ae\roms.... ae.d2 NO MATCH ae.e5 NO MATCH ae.e8 NO MATCH ae.f2 = pr-1538.55 monsterb2 Monster Bash (2 board version) = f14 skyfire Sky Fire ae.g1 NO MATCH ae.g2 NO MATCH ae.h2 NO MATCH ae.j2 NO MATCH Both chips had the same pinout except for pin 15 Final pinout used to read the chips as a 2764 A7 VCC A8 D0 A9 D1 A10 D2 A0 D3 A1 D4 A2 D5 A3 D6 A4 D7 A5 A11 A6 GND GND Invert of /OE from 2764 Only saved 12 bits off address since there was no room for A12. A11 looks like another enable line, since data is all 0's when it is high. Mame .283 C:\Siftware\roms>c:\games\mame_command\mame -romident c:\siftware\roms\ae\roms Identifying c:\siftware\roms\ae\roms.... ae.b4 NO MATCH ae.b5 NO MATCH ae.d2 NO MATCH ae.e5 NO MATCH ae.e8 NO MATCH ae.f2 = pr-1538.55 monsterb2 Monster Bash (2 board version) = f14 skyfire Sky Fire ae.g1 NO MATCH ae.g2 NO MATCH ae.h2 NO MATCH ae.j2 NO MATCH