NP-41 Emulator (may be)

[Chris Chung]

(01-25-2016 01:45 PM)jch Wrote:  Chris,
I just looked at your 'Just another image test' thread.
(Edit : In between you updated the thread ;-))
It's really amazing.
Though some members may miss the original 14 segments LCD, I find the COG LCD display very cool.
I can see many advantages using it : lowering I/O pins, very nice stack display...
About the thickness, what about putting processor and connector on the other side of the PCB, under the display ?
Many thanks for this smart emulator.

Jean-Christophe.

Thanks for your comment. I enjoy doing this project as well.

I am going to build both the segment version and the COG version. As a matter of fact I am using the same project source w/ compiler directives for different MCU and LCDs.

The "Slim" version has a good chance to make into a kit as it will be relatively easy to build. And I think it could be made into an everyday-carry calculator.

I was thinking the same regarding the layout. Having all components on one side would be a lot cleaner. Except that I am hesitate to place the MCU under the display as it will increase thickness and disable trouble-shooting / repairs. I am imagining a layout that places the top 4 buttons (ON, USER, PGRM, ALPHA) as 2 x 2 and on one side, where the CR2032 will be placed on the other side. And the MCU can be in the middle. I will fiddle w/ a PCB design to see how it looks.

Also I would like to reserve space for pin connectors to facilitate firmware update and a USB-Serial connection. Would like to build a program loader (HP-41C programs) for transferring programs.