IC Identify from DENSO EFI controller.. help?

[Jerry Wills]

Hi Folks,
	 I opened up my SD EFI box from a GTS1000 YAMAHA (detuned 1000cc
motorcycle engine) with 10,500 rpm redline. I've Identify a few of the
big chips, the small ones are standard HC logic. Here is what I have so
far.

Hitachi HD63B40P  28DIP  6800 programmable timer
         but no second source or data sheet available from IC master or Hitachi

Hitachi	HD63B21P  40DIP  6800 PIA
         but no second source or data sheet available from IC master or Hitachi

ND      MG2530    40DIP   ?

ND      MG614     16-20 DIP   I didn't write it down, thought I had the 
				memory chip covered with the 28 pin part.

The Nippon Denso chips didn't appear in the IC Master and Hitachi was little help.
Looks like I'll need some old data books, from around 91

This unit was put into service in 93. The outside of the box has this on it,
for what its worth




		4HH-8591A-00

		122100-0040
				   I\
		12V    TBDF03	   I \
				   I  |  Thats a large "D"
				   I /
	   ND  DENSO     JAPAN     I/




	 Hand written in felt BELOW


		  3252





This is a 2 sided PCB, no interlayers, so following the traces is easy.

The point to this abuse is that 94 GTS's has an updated program and are
much smoother on deceleration and don't surge at idle. I thought that
update exercise was in order and with thru-hole parts, adding sockets 
and removing parts intacted isn't difficult to do.

Thanks,
	Jerry