A serial-fed operating system selector switch for GRUB built on the ATTiny85.
This will listen for a phrase being sent in over serial and send a series of keystrokes back if it picks up the correct phrase.
I run both Linux and Windows simultaneously on my main PC using GRUB2 as my bootloader. By default GRUB will boot into Linux, but I have to wait ~10s from powering on before GRUB will let me choose my OS. I'd much rather flip a switch and walk away while it boots into my OS of choice, so here we are.
This is built to run on an ATTiny85 connected to an MSI Z97S Krait Edition motherboard through the JCOM1 header. It might work with other boards, YMMV.
You'll need:
- An ATTiny25/45/85
- A PC with a serial port
- A MAX232 (optional, for logic level conversion)
- An ISP that can flash an AVR (I used a USBtinyISP)
makeavrdudeavr-gccandavr-libc
Open the Firmware directory and run make.
There are a couple of make targets:
make fuse: Burns the fuses into the AVR
make flash: Flashes the firmware
make clean: Cleans up build artifacts
Chip-specific settings (fuses, clock speed, ISP, etc.) are defined in the makefile and should be modified to suit your environment.