WheatSystem operating system

WheatSystem is “neoretro” (I made the word up now) portable operating system


for the author’s WheatBox, a handheld 8-bit computer:


There is also a YouTube presentation: WheatSystem: A Homebrew Operating System - YouTube


Nice! Here’s a photo from the second link:


Interesting. It reminds me of this:


And interesting little “eco system” They’re building - based on the 8-bit ATmega328 (same MCU as “classic” Arduino boards) with some SPI storage.

Reminds me of the Fignition system which was similar hardware but had a chorded keyboard and drives composite video.



With the modern micro controlers, do you get to use bare metal or is that hidden as
Intelectual Property? How big would a CMOS 6502 version be?

The 8-bit MCUs like ATmega, PIC, etc. are generally fully open, so bare metal is a thing - technically it’s always a thing as you can boot directly into your own code without a bootloader being needed at all. (Which I do on all my systems)

Once you get more complex MCUs then it starts to get harder, but lots of the little ARM systems are very bare-metal friendly as well as some of the RISC-V ones. Even the Raspberry Pi is (now) easy-ish to do bare-metal with. The issue (for me) is that the more complex the system is, the more code needs to be written to actually make the thing work - e.g. the USB and SD card hardware built into the Pi’s SoC is just big and ugly. Sometimes you to get binary ‘blob’ softwares - the ESP systems are like this so you link them into your own thing to use e.g. on-board Wi-Fi, etc.

Making one of these Wheat" systems with a 6502 would be interesting and very do-able. You might need a few more ‘glue’ chips though as the ATmega has lots of goodies on-board like serial, PWM, ADC, I2C and SPI. The Wheat OS appears to be able to execute a bytecode rather than run native ATmega opcodes (which is actually quite hard as it can only run native code from the on-board flash - Harvard Architecture and all that and while you can re-program in on the fly, (e.g. how a bootloader works) I don’t know anything that does that for a run-time environment.


I see - I think - that the long-term vision is for a self-hosting OS, something that I always find very attractive.