DuPAL

WIP

Pre-compiled: https://proghq.org/media/dupal/

Building

Optiboot

# https://github.com/Optiboot/optiboot

# 328P uses 115200?
# a few use 57600 but not the one we need :(
# wget https://github.com/Optiboot/optiboot/releases/download/v8.0/Optiboot-8.0.zip

git clone https://github.com/Optiboot/optiboot.git
cd optiboot
git checkout -b v8.0 v8.0
cd bootloaders/optiboot
make atmega328 AVR_FREQ=20000000L LED_START_FLASHES=8 BAUD_RATE=57600

Flash optiboot. Example CLI to use ISP header, but can also put into tl866 etc:

avrdude  -c dragon_isp -P usb \
   -p atmega328p -e -u -U efuse:w:0xFD:m -U hfuse:w:0xDE:m \
   -U lfuse:w:0xFF:m -U flash:w:optiboot_atmega328.hex