This is my first project here, and it's a pretty stupid one. Ostensibly, this is to enable myself and other people to modify the hardware on the CE more easily, but in reality, It's mostly because I'm bored. and want to do something at least slightly interesting. I'm not experienced enough with calculator stuff to create any actual hardware mods myself, so my goal with this is purely documentation, and to apply the skills that I do have (EDA) to the hobby of calculators, which I've been fascinated in for a long time.
tl;dr I want to use the skills that I do already have to make an inroads with this hobby and community because it seems pretty cool.

Anyway, here are my goals:
Create a complete schematic of the CE's main board
Create a bill of materials and board layout in KiCAD
Upload it here

Goals I might do if I want to continue this project:
Create files for Fritzing and EagleCAD
Create some simple hardware mods
Create 3d models of all the components of the CE

I will post updates here, expect some very soon.

EDIT: This will be based on HW revision N, since that's the revision that I have. I might also do this for other revisions if I get that far.

Good luck with the project.

Having removed the board from its plastic tomb, (Sidenote: the board being melted in place is easily overcome with extreme patience and an X-acto knife.) I originally intended use the amazing work done by DrDnar on this thread.

However, I am using a different hardware revision, and I also needed to get a flat image of the keypad side of the board. I am not at all skilled in photography. I scanned it in a photocopier and sent it to my computer. It absolutely feels like cheating, especially as compared to the painstaking effort that DrDnar took, but there are loads of issues with this method that are absolutely going yo haunt me later on, such as the slight upward tilt caused by the uneven height of the components, and the board being slightly out of focus from being a bit farther away.

Anyway, here are the images.
https://imgur.com/a/ltCyk8o

I'll probably wind up desoldering everything and getting a better scan, but my schedule is pretty tight at the moment, and I need a working CE, and since my chances of resoldering a QFP are pretty slim, I'll need to buy a new one while also knowing it's hardware revision in advance.

See ya later I guess