USBasp programmer

USB in-circuit programmer for Atmel AVR controllers. It consists of an ATMega48 and a couple of passive components. The programmer uses a firmware-only USB driver, no special USB controller is needed.
This variant is for 3.3V circuitry.



DiagramUSBaspprogrammer.png

Optional socket board schematic is included in download archive.

Short description

This schematic is a bit simplified from original one. Differences are: used here ATMega48 must be initially programmed via another programmer, for example with PonyProg2000 because there is no connection between RESET and SS; only ATMega48 (not ATMega8) can be used as it works with 3.3V power supply at 12MHz. Future serial interface is not implemented and will not work at all because there are no connections with RXD, TXD and ISP connector. Pin layout of ISP connector on socket board is different from one specified by ATMEL.

Necessary files and their usage

- USB_programmer.sch, USB_programmer.pcb, USB_programmer_extension.sch, USB_programmer_extension.pcb - circuits and board layouts for programmer itself and optional socket board.
- usbasp.atmega48.2009-02-28.hex - firmware. Upload it into ATMega48 with another programmer.
- win-driver - folder with USB drivers for Windows. Specify it when prompted (after you plug USB cable into computer).
- eXtreme Burner - AVR - GUI program for loading HEX files (firmware) into AVR microcontroller.

USBProgrammer.zip