Zengrange Zeprom Question


I just picked up 2 SMI Surveyor-41 CO-OP modules that are identical except one is labeled Zengrange and one is not. I can feel the "erasing window" under the sticker on the Zengrange labeled module, but there is no window on the other one.

Question is: Can someone identify the non-Zengrange module? Is it an MEPROM?

Cat 2 returns CO-OP ROM for BOTH modules...

Edited: 10 Nov 2012, 12:29 p.m.


Can you provide pictures of the other module? If it has a small opening on each side, then it could be a CMT EPROM. If the module housing looks exactly like a normal HP module, then maybe it's a mask programmed ROM made by HP.
As an example, the CCD module version A programmed by W&W was manufactured by HP, the version B was made by W&W inhouse using CMT EPROM mdules.




Looks like there is a hole in the side:

Edited: 10 Nov 2012, 3:20 p.m.


Thanks for the pics. It is a CMT EPROM.

The EPROM chip is standard, but to reach the pins you'll need a special programming adapter, which is next to impossible to get.



Thanks Ray,

I'm going to toss these up for auction. I appreciate the knowledge so I can accurately describe them.


Edited: 10 Nov 2012, 7:07 p.m.

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