Cpu hd6475388f10

I repaired the instrumentation equipment found the CPU broken, then replaced by
the same chip p/n HD6475388F10 made by Hitachi,it is work but intermitent.
I thought may be the chip specification does not match, so I want to know who made the existing chip
the mark on the chip are :

HD6475388F10
H8/538
0642
TK 32054

as I know there are 3 manufacture make this chip : Hitachi, Renesas and HIT.
Thank for your help.

This is a complete microcomputer chip, without original software cannot work. The brandnew chip is totally blank.

Hi Sebi,
if the CPU status operate in mode-3, maximum expanded and PROM disable , may I said that
the internal program is disable also , and the program only use the external ROM only ?
Thank for your repply.