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HP Forum Archive 14

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Upgrade card for 41CV
Message #1 Posted by Mike H on 6 Oct 2004, 5:33 p.m.

Saw an interesting item on eBay, an upgrade card to change a CV to a CX. Has anyone seen these before. I wonder if it has the time applications

It will not make a CV into a CX
Message #2 Posted by Randy on 6 Oct 2004, 6:03 p.m.,
in response to message #1 by Mike H

You're only getting half the story:

You'll get time functions but you will not have a full CX, only a CV with "Time" and "CX Time" functions. To have a CX you need the extended memory functions which are in the rom contained within the lcd module. Parts not included.

And now the really big omission: The module will only fit in a halfnut version unit.

Edited: 6 Oct 2004, 6:05 p.m.

Re: It will not make a CV into a CX
Message #3 Posted by Tony Duell on 7 Oct 2004, 7:03 a.m.,
in response to message #2 by Randy

The service manual is not particualarly clear about this, but I believe the extended functions ROM and the extended memory RAM are in this module (along with the timer chip, crystal, time functions ROM, etc).

_HOWEVER_ the 41CV main ROM (which is in the LCD driver hybrid) will not look for the extended functions ROM. If yo add this module to a halfnut CV, then you get the time functions, but not the extended functions (I have actually done this to see what would happen).

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