I'm trying to program my ATtiny85 with Atmel ICE but I get this error:

avrdude: stk500v2_command(): unknown status 0xcc avrdude: initialization failed, rc=-1 Double check connections and try again, or use -F to override this check.

Does anyone know what problem is?

  • \$\begingroup\$ Schematic for your board, please. \$\endgroup\$ Commented Jun 16, 2017 at 16:27
  • \$\begingroup\$ What avrdude command are you using? \$\endgroup\$ Commented Jun 16, 2017 at 18:16
  • \$\begingroup\$ Are you providing 5V to the ATTiny? (The Atmel ICE doesn't supply power) \$\endgroup\$ Commented Jun 16, 2017 at 18:18
  • 4
    \$\begingroup\$ I'm voting to close this question as off-topic because it has been abandoned in unanswerable condition for two years \$\endgroup\$ Commented Jul 24, 2019 at 17:03
  • 2
    \$\begingroup\$ The two problems are that as an abandoned question it will likely never have an accepted answer. And as a terribly incomplete question it's an example of what NOT to do when asking - especially where the specific requests for clarification were ignored. \$\endgroup\$ Commented Jul 24, 2019 at 18:13

1 Answer 1


Common causes for this:

  1. Atmel ICE doesn't supply power to the microcontroller (as Tom mentioned in comments). It has a green LED that indicates target power, but you need to supply power separately.

  2. Make sure the RESET pin is not being held high by other parts of your circuit. The Atmel ICE needs to be able to pull it low during programming.

  3. Double check connections - just as the error suggests. I've been guilty of having MISO and MOSI swapped, having a loose wire, and having the microcontroller inserted into a breadboard backward.

  4. Make sure that the fuses haven't been set to prevent writing to the microcontroller. A good example is the RSTDISBL fuse. If that has been set, you have to use a high voltage programming mode to get around it.

  5. Swap the microcontroller out for a known working one. It's possible that the one you're trying to program has died (from static, high voltage or current, etc).


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