ZEPROM module ?


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


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:

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.


Possibly Related Threads…
Thread Author Replies Views Last Post
  HP-41 CMT EPROM & ZEPROM Programming Dan Grelinger 3 1,478 11-26-2012, 02:42 AM
Last Post: Diego Diaz
  Zengrange Zeprom Question aj04062 4 1,647 11-10-2012, 07:06 PM
Last Post: aj04062
  Re: Anyone build a ZVC (Zeprom Voltage Converter) Continued - 2 Dan Grelinger 4 1,566 07-26-2008, 10:52 PM
Last Post: Scott Newell
  ZVC ZEPROM Voltage Converter (continued) Dan Grelinger 21 5,011 07-26-2008, 12:45 PM
Last Post: Muhammad Ahmad
  ZEPROM Auction Problems Explained Dan Grelinger 0 667 07-13-2008, 07:04 PM
Last Post: Dan Grelinger
  Anyone build a ZVC (Zeprom Voltage Converter) Dan Grelinger 13 3,236 07-12-2008, 03:31 PM
Last Post: Muhammad Ahmad
  Bug in ZEPROM PROGRAMMER code? or HP-41CX? Dan Grelinger 0 816 07-02-2008, 10:57 AM
Last Post: Dan Grelinger
  ZEPROM (for HP-41) at Ebay ? Ray Colle 7 1,763 06-04-2004, 09:40 AM
Last Post: Ángel Martin
  Zeprom & BankSwitching Emmanuel, France 2 1,110 12-07-2003, 03:08 PM
Last Post: Emmanuel, France
  zeprom Poul 6 1,659 03-19-2001, 07:09 AM
Last Post: Georg Lahm

Forum Jump: