MicroDOS - a simple loader for PSRAM based system
We have more and more toys like NeoYume and the standard way of uploading them from PC is less and less convenient. So I made this loader. This is a first, crude, but working, version of it.
The loader searches for binary files in /sd/microDOS, lists them and allows to select and load the program. It uses hacked version of PSRAM driver, where I moved mailboxes to $7F000. After the Enter key pressed, MicroDOS loads the binary to PSRAM, stops all cogs except PSRAM driver and runs a cog which moves the binary from PSRAM to HUB. The cog then stops the PSRAM driver, inits the cog #0 from address #0 and stops itself.
The name of the program comes from the 8-bit Atari world. Atari microdos boots from the floppy disk, then searches and lists executable files on it.
There are no standard way to attach a keyboard, so if you want to play with the program. you have to replace my "retrocog.spin2" which uses the RPi based serial kbd interface with your keyboard driver, and add a "readkey" function to it so the main program can call it and read a pressed key code.