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HP Forum Archive 14

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41cx doesn´t recognise 319 registers
Message #1 Posted by Gonzalo Fernandez on 28 Nov 2004, 11:28 a.m.

I have an HP41cx fullnut that after doing SIZE 000, shows only 255 (it is missing 64 registers). I have reset the calculator with no luck, only shows 255 registers instead 319 registers. Also, EMDIR shows 124, so extended memory is OK. What memory chip/chips (upper, lower or both) I must change to repair the memory? Please see the photo http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=5733774885&ssPageName=STRK:MEWA:IT

to let me know which of the 5 top memory modules I must change (each memory module comprised with two soldered chips)

thanks!

      
Re: 41cx doesn´t recognise 319 registers
Message #2 Posted by Miki Mihajlovic on 28 Nov 2004, 10:56 p.m.,
in response to message #1 by Gonzalo Fernandez

According to the service manual figure 4-8f, table 4-5f and Diagnostic Test Procedure outlined on page 4-31 the D/S 5 is bad, which is U9. That should be the upper chip first from the left one that reads 1LH505.

1234

Edited: 28 Nov 2004, 10:57 p.m.

            
Re: 41cx doesn´t recognise 319 registers
Message #3 Posted by Gonzalo Fernandez on 29 Nov 2004, 4:12 a.m.,
in response to message #2 by Miki Mihajlovic

Thank you very much for your responses!


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