Host System
Emulator:
Fake86, is a (great!) portable, open-source 8086/80186 PC emulator written by Mike Chambers from the ground up in C: https://sourceforge.net/projects/fake86
Mike also tried it on Arduino Mega with serial console output and later a custom PC client.
That inspired me to run it on EduCIAA (as my previous ZX Spectrum emulator) only with a TFT display and no aditional memory.
EduCIAA:
Prouddly using EduCIAA, a board designed in Argentina by Argentinians, is an educational version of the major CIAA, an industry oriented, open computer.
I used the NXP version, based on LPC4337, an ARM Dual Core microcontroller with M4 and M0.
Display
ILI9341 is a 320*240 pixels, very cheap, TFT. I used an SPI interfaced one, so some software improvements were implemented to minimize (slow) data traffic.
As with my ZX Spectrum emulator display write operations are reduced mantaining a last frame
copy
Emulated System:
As EduCIA has 1024KB Flash memory and 196 KB RAM the emulated PC has:
Read Only Floppy Disk: A floppy image (up to 360KB ) contained on Flash Memory, as constant array.
112KB (conventional) RAM
CGA: As TFT has 320*240 resolution the implemented modes are: 40 columns text and 320*240.
80 cols text is (forced) displayed as 40 cols.
BIOS
The used BIOS is wide available and only was customized in order to limit RAM to 112KB, as the included automatic size determination crashs the system.
Display is ILI9341 TFT (SPI).
No external (aditional) RAM, so emulated PC has only 112KB of conventional memory and CGA, but enough for DOS (up to 3.30), CP/M, DOS games, Logo and of course IBM ROM Basic.
EduCIAA is an ARM Cortex M4&M0 based board designed in Argentina: http://www.proyecto-ciaa.com.ar
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