ZEPROM module ?

[Paul Dale]

I've got a HP41 module which I've got an inkling as to what it is but not how I could use it/what it is good for.

The module has a clear window with what looks like an EPROM showing through. There are no identifying marks or text on the module, although "828/89" has been lightly scratched next to the EPROM window.

When I plug the module into my 41cv and turn the unit on, a message "ZEPROM TEST" appears on the display and the numeric flag annunciators turn on in turn (1, 2, 3 & 4) with each displayed for 8 or so seconds. Finally a "TESTS PASSED" message is displayed and a keystroke allows normal operation of the calculator.

I don't notice any changes in any of the catalog listings (although I've not inspected the CATALOG 0 listing in any detail).

A google for ZEPROM isn't overly helpful.

Can anyone tell me what I've got and how to use it?
I don't have a programmer so I doubt I'll be able to do much with it.

- Pauli

[Matthias Wehrli]

What you have is a ZEPROM module, yes. Yours seems to be a new and not used one as we can buy it from of seller at ebay. If you want to programm it you need a programmer. The module itself accepts 16k of "information". To erase the contend of the module you need a UV eraser as this module works like a "normal" EPROM, but only in module shell.
There are at least three sorts of programmers. Please have a look at my website for that:
http://www.hp-collection.org/41accessories.html

There are a couple of people in that forum who have a programmer and could programm it for you. As there are more powerfull options in the meantime I would keep it untouched and use a MLDL2000, Clonix, NoVRAM or anything else. That´s what I do with about a dozen of new ZEPROM modules.

Matthias
www.hp-collection.org