The following list was written by user202729 and serves as the guide to this forum thread.
Tutorial about ROP.
Scrolling text demonstration with video.
How to enter a hackstring (991ES+) (less detailed version)
Hackstring used to dump the ROM. No longer needed now as we already have the ROM.
Datasheet contains some information about the hardware.
Hardware description: Part 1, part 2.
* KI/KO ports (keyboard).
* Timer: Part 1, part 2.
* LCD screen.
Variable byte representation (no English translation this time).
There are some outdated information about "real address" and "emulator address". Now we had the real ROM of the calculator that is not necessary.
Edited by SopaXorzTaker, 28 February 2018 - 03:22 PM.
Add user202729's markdown version