This is a USB AVR programmer based on the design by Thomas Fischl. I used the Eagle files by JA de Groot and changed them to suit a standard 6 pin Atmel AVR ISP header.

Schematic and PCB

In renumbering the components, the jumper numbers changed from the original. The functions of the jumpers are:

J1 Self Program: Set this jumper for flashing the ATMega(4)8 of USBasp with another working programmer.
J2 Slow Clock: If the target clock is lower than 1.5 MHz, you have to set this jumper. Then SCK is scaled down from 375 kHz to about 8 kHz.
J3 Board Power: Supply target with 5V (USB voltage). Be careful with this option, the circuit isn't protected against short circuit!

You should look in the "/AVR Projects/AVR ISP USBasp" folder.


The software is not mine. You get the software from the author's website.