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Forum: General Discussion
 Topic: CP/M on a small board with touchscreen
CP/M on a small board with touchscreen [message #4716] Sun, 20 May 2018 05:55
dr_acula is currently offline  dr_acula
Messages: 59
Registered: October 2015
Location: Adelaide
Inspired by this project kaday-belgrade-has-everything-you-wished-for-back-in-the-day / I started thinking about CP/M with a touchscreen. Sadly, those boards are on a limited production run, so maybe there are ways to do something similar with off-the-shelf components?
I've got lots of CP/M boards, some running on real chips, some as emulations and some on FPGAs. More lately, I've been playing around with this project Two things that make this attractive: 1) it works right out of the box with no soldering needed, and 2) CP/M can read fat32 files straight off an SD card, so no need to play around with disk images. needs a display! There are lots of choices, and I am looking for software and hardware that needs minimal extra work. and more at This runs very fast and only took a few minutes to get working. The Due and the touchscreen both run at 3V3, so the only soldering was the dropping resistor for the backlight.
Search on ebay for ILI9341 displays and there are ones that are 2.4" and also 2.8", and there are ones for only about $10 that also include a touchscreen and the SD socket.
What would be really cool would be using Wordstar, and this really needs an 80 column display. If a display is 320 pixels wide, that only is 4 pixels per character, and one of those is the space between characters. There are some legible fonts only 5x3, eg and I think the c font array data can be found with a search for newbasic3x5.h
It should be possible to draw a picture of a keyboard on the screen, and then use the touchscreen as input.
An Arduino Due can do a lot more of course - add wifi, an ethernet shield, lots of serial ports, analog and digital IO (lots of spare pins), and libraries already written for all this so it is easy to add peripherals.
This project is currently just a collection of pieces of software that all seem to work independently, and it is now a matter of bringing it together. In terms of hardware, it is an Arduino Due board ($18) and a touchscreen ($11).
Thoughts etc would be most appreciated!

Current Time: Sun May 20 12:42:42 PDT 2018

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