Hello

I'm trying identify old RICOH RF5A93 uC. Cannot find any info in the 
net. This is exteral memory QFP100 chip, at least 1998 year of 
production.

I downloaded code but this instruction set is new to me and still don't 
know what it is. I wrote simple program to count which bytes are most 
popular and this is what I got:

1/ 0xE0
2/ 0x08
3/ 0x0A
4/ 0x0B
5/ 0x10
6/ 0x01
7/ 0x0C
8/ 0x0E
9/ 0x90
10/ 0x02

Can anyone can help me identify this code?