Biplane? by Fun Games

.6	82s115	stamped	12345
.7	82s115	stamped	12346
.8	82s115	stamped	12347
.9	82s115	stamped	12348

.6 would always read the same checksum, but would return verify failed.
	I am using a Data I/O Series 22 to read them and it's not clear what failed means.

Mame 0.279
C:\Siftware\roms>c:\games\mame_command\mame -romident c:\siftware\roms\bp1\roms\bp1.6 
Identifying c:\siftware\roms\bp1\roms\bp1.6....
bp1.6                NO MATCH

C:\Siftware\roms>c:\games\mame_command\mame -romident c:\siftware\roms\bp1\roms\bp1.7 
Identifying c:\siftware\roms\bp1\roms\bp1.7....
bp1.7                NO MATCH

C:\Siftware\roms>c:\games\mame_command\mame -romident c:\siftware\roms\bp1\roms\bp1.8 
Identifying c:\siftware\roms\bp1\roms\bp1.8....
bp1.8                NO MATCH

C:\Siftware\roms>c:\games\mame_command\mame -romident c:\siftware\roms\bp1\roms\bp1.9 
Identifying c:\siftware\roms\bp1\roms\bp1.9....
bp1.9                NO MATCH