I’m using an arduino nano.

Way easier than wiring up my own bullcrap, even though I’ve got some raw chips and a programmer on hand.

Here’s a short makefile that will get stuff to happen. You’ll need to replace /dev/tty0USB0 with wherever you’re device actually is.

TARGET=led

all: $(TARGET).c
	avr-gcc -Os -DF_CPU=16000000UL -mmcu=atmega328p -c -o $(TARGET).o $(TARGET).c
	avr-gcc -mmcu=atmega328p $(TARGET).o -o $(TARGET)
	avr-objcopy -O ihex -R .eeprom $(TARGET) $(TARGET).hex

flash: $(TARGET).hex
	avrdude -F -V -c arduino -p ATMEGA328P -P /dev/ttyUSB0 -b 57600  -U flash:w:$(TARGET).hex

This was useful in figuring out how to make this makefile.

#include <avr/io.h>

int main(void)
{
    // connect led to pin PC0
    DDRB |= (1 << 0);
    while(1)
    {
        PORTB ^= (0xFF << 0);    // toggles the led
    }
}

This makes a fast switching program just to see what we can pump out. I measure 1.6Mhz

avr-objdump -m avr -D fastswitch.hex > assembly

Also

Adafruit Shield version 1 works on my chinese DK electornics board. Nice.