HP 41CX math and X memory problems

[Jlouis]

(11-24-2018 10:01 PM)rprosperi Wrote:  The X-Memory module is never seen in CAT 2. An X-mem module simply adds more extended RAM for the built-in Extended Functions to manage (the CX has the Ext Functions/Memory module built-in).

CAT-4 returns the amount of X-Memory available to the X register. Try this with and then without the X-Mem module inserted and you should see different results. If they are the same then either the module or the slot you are using is bad. Try other slots.

If the Math ROM is not seen in any of the slots, the module is probably bad. The fact that the printer and Adv ROM work confirms those slots are good - try rotating ports and see if there is a pattern.

For both modules, if they have been sitting for a long period, especially not inside a 41C, it's possible oxidation has built-up on the contacts, just like any other device. Try CAREFULLY cleaning the contacts with DeOxit RED (I use Qtips with much of the cotton pulled-off before starting).

It's also possible the 'bad' ports inside need to be cleaned, but do so carefully here as well - the blade you push the module onto is sturdy, but the leads on the folded connector sheet can be torn if they are badly oxidizing.

Thanks for the reply Bob.

The X memory is working good, I did further read in the manual showed that we need to press the arrow key for the available x memory.

As for the math module, I will do the cleaning you suggested.

This is only for curiosity, as I have the marh/stat Pac and really don't need another math.

Thanks again.

Cheers

JL