|Would someone check an HP41C halfnut, please? (and a new image)|
Message #1 Posted by Vieira, Luiz C. (Brazil) on 27 May 2003, 11:44 a.m.
HI, HP41 maniacs (like me);
if there is any HP41C halfnut owner reading and with necessary skills, would you please open it and check for the hybrid LCD driver code?
I'd like to know if there are only two of these IC's - 41CV and 41CX - or if the 41C halfnut has a different one. Let me explain why.
When the first halfnuts became available, the HP41C was no longer being produced. Anyway, I read here in this very formum, that some units were released for replacement purposes. This means that the same mainboard is used for the HP41C.
As I have an HP41CV that fails to recognize more than 63 registers and the hybrid IC has the same code of another fully-operating HP41CV halfnut, I am trying to get to conclusion if this hybrid IC is defective or if there is some sort of jumper in the mainboard that would restrict the access to the remaining memory.
I compared this halfnut mainboard to another 41CV halfnut mainboard (newer) and found an additional SMD with an N2(with a slash over both characters) as identification, and it goes straight in two terminals of the hybrid chip. The other mainboard has the pads for soldering it, the one I scanned and posted here doesn't. I thought about removing it and testing it to see what sort of component it is, but I prefer waiting a bit more till I have other references. If there is a third hybrid chip for the HP41C, I will conclude this 41CV is definitely damaged.
The new, additional image is the one that shows the back image of the halfnut LCD. I forgot to add this image to the set shown in my previous post.
Thank you for any additional information.
Luiz C. Vieira - Brazil