The Leon system 11/data east chip from pinwiki anyway is supplied on a 27512 chip. It looks like it's just a doubled up 27256 image though, I split it in half and both halves verified with each other.

Looking at the code split in pinmame, there are 3 bytes starting at offset $257 that are 00 00 00 - this is an illegal opcode. Now, pinmame just skips right over these because it might not be 100% cpu accurate, or a later revision cpu fixes this error (illegal opcodes usually do something unpredictable in a microprocessor).

You can change those 3 00 bytes in your editor to be "01 01 01" which is the 6800/02/08 opcode for "nop" (no operation) and see if it works that way.

Looks like that's a different version of the chip then what I downloaded from pinwiki. Pinwiki's said it was version 5, and your offset is the text part (which is never executed).

Pintec can you compare what you have to what is on pinwiki - seems like the pinwiki one might be wrong as there shouldn't be 3 illegal opcodes in the middle of the test. The pinwiki is a 512 image but it's just a doubled up 256.