What's new
No, 27C64 isn't rewritable, it's an UVPROM.

[EDIT]
I meant you can't rewrite it in situ as expected for a 28C64. The 27C64 has to be UV erased first.
 
Last edited by a moderator:
Thanks mate. Thrown of by the picture on Jaycar.

I tried rewriting it but no dice. Doesn't pass the test screen stating it's no good. If I pull one from a working board no issues.

What does it do? Save settings? If I purchase another one do I need to program it?
 
It saves high scores IIRC.
I believe if a blank one is inserted it's automatically "formatted" upon next boot.
 
That's what I was thinking.

Will need to find and order one and I'll let you know...
 
So following up on this in the unlikely case it's useful for someone in a similar position...

To briefly recap, MT2 coming up with EEP NG on bootup.

I thought it was stuck on this screen but since discovered a few button presses bypasses this screen and the game proceeds to run normally.

I purchased and fitted an AAT28C64B-15PU. It didn't work, same error message appeared. I mashed the controller in frustration and it then displayed the following screen:
IMG_20200602_163526.jpg

I let it do it's thing and after some time the game ran normally. Sadly, a hard power cycle yielded the same EEP NG error being reported by the startup test sequence.

I then refitted the original NEC 28C64 chip, invoked the restoration process and voila, problem solved. It's now working 100%.
 
Back
Top