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[on:]

Hey guys,

I am going to buy a cheap USBasp (ISP Programmer). I want to use it with AVR Studio and therefore flash the bootloader from Christian U. onto it (http://www.ullihome.de/wiki/USBAVRLab/ullihome#USB_AVR-Lab).

Is it possible to flash the bootloader via Arduino ISP (http://arduino.cc/en/Tutorial/ArduinoISP)?
How can I connect the Arduino to the Atmega from the USBasp? (or if Arduino doesnt work, the ISP programmer)
http://dx.com/p/usb-isp-programmer-for-atmel-avr-atmega-attiny-51-board-148046
This is the one I am going to buy (ofc i'm gonna remove the heat shrink tube before ;D)

greetz

fran83

[Reply #1 on:]

The ICSP connection is MOSI, MISO, SCK, VCC, GND, and RESET.  Five out of six of those signals are on the ICSP connector on the USBasp.  The RESET line on the ICSP connector is an out out pin from the processor to drive the RESET input of the target machine.  It is not connected to the RESET line of the USBasp. You will need to locate the RESET pin of the ATmega8A processor on the USBasp.  That's pin 29 counting counter-clockwise from the dot or the 4th pin clockwise. On my USBasp it appears to be connected to a empty jumper marked J2.

Readme - fischl.de
www.fischl.de/usbasp/Readme.txt
"J2 Jumper for firmware upgrade (not self-upgradable)
   Set this jumper for flashing the ATMega(4)8 of USBasp with another working
   programmer."

I think that mean you can put a jumper (solder blob) across J2 and it connects the RESET output pin to the RESET line so you can use it for an input.  With the jumper in place you can use an ISP connected to the ICSP connector to burn fresh firmware.

[Reply #2 on:]

The ICSP connection is MOSI, MISO, SCK, VCC, GND, and RESET.  Five out of six of those signals are on the ICSP connector on the USBasp.  The RESET line on the ICSP connector is an out out pin from the processor to drive the RESET input of the target machine.  It is not connected to the RESET line of the USBasp. You will need to locate the RESET pin of the ATmega8A processor on the USBasp.  That's pin 29 counting counter-clockwise from the dot or the 4th pin clockwise. On my USBasp it appears to be connected to a empty jumper marked J2.

Readme - fischl.de
www.fischl.de/usbasp/Readme.txt
"J2 Jumper for firmware upgrade (not self-upgradable)
   Set this jumper for flashing the ATMega(4)8 of USBasp with another working
   programmer."

I think that mean you can put a jumper (solder blob) across J2 and it connects the RESET output pin to the RESET line so you can use it for an input.  With the jumper in place you can use an ISP connected to the ICSP connector to burn fresh firmware.

Thanks for the quick response!

So I basically just have to connect the pins 1, 2, 4, 7, 9 (MOSI, VCC, GND, SCK, MISO) from the 10 pin connector on the programmer to the appropiate pins on the Arduino (according to the Arduino ISP tutorial)? And I think on the USBasp clone I linked to you can see a black jumper. Maybe it is the one for the reset pin?

[Reply #3 on:]

So I basically just have to connect the pins 1, 2, 4, 7, 9 (MOSI, VCC, GND, SCK, MISO) from the 10 pin connector on the programmer to the appropiate pins on the Arduino (according to the Arduino ISP tutorial)?

You also need the RESET line.  That's why the "J2" jumper exists: to turn the RESET output pin into a RESET pin so you can re-program the processor.

And I think on the USBasp clone I linked to you can see a black jumper. Maybe it is the one for the reset pin?

The jumper is labeled J2 but it would be very unusual to re-program the chip so my guess is that the "J2" jumper on that USBasp is NOT the RESET jumper.  I would guess it is a jumper to optionally supply Vcc to the output connector.