Arduino High Voltage Programmer / Eraser for ATtiny

Based on Recover Bricked ATtiny Using Arduino as high voltage programmer.
This program restores the default fuse settings of the ATtiny and can perform a chip erase & lock bits reset.
After resetting, the fuses can then easily be changed with the programmer you use for uploading your program i.e. avrdude.
To burn micronucleus bootloader on an empty chip use the Burn_avrdude-* scripts available here.

Modified for easy use with Nano board on a breadboard

• Added option to press button instead of sending character to start programming
• Improved serial output information
• After programming the internal LED blinks
• Added timeout for reading data
• Allow Serial command input
• Added readout of lockbits
• Added Chip Erase

Installation

Just copy the content of the HVProgrammer.ino file into a new Arduino sketch and run it.

In the Arduino serial monitor with baudrate 115200 you will see something like:

START C:\...\ArduinoSketches\sketch_jun15a\sketch_jun15a.ino
Version 3.2 from Jun 15 2019

Enter 'r' to only read fuses and lock bits...
Enter 'e' to erase flash and lock bits...
Enter 'w' or any other character or press button at pin 6 to to write fuses to default...

and after button press or sending a character you see for an ATtiny85:

Reading signature from connected ATtiny...
Signature is: 930B
Reading signature complete..

The ATtiny is detected as ATtiny85.

Reading fuse settings from ATtiny...
  LFuse: 62, HFuse: DF, EFuse: FF
Reading fuse values complete.

Reading lock bits...
  Lock: FF
    LB1 Not Programmed
    LB2 Not Programmed
No memory lock features enabled.
Reading Lock Bits complete.

Write LFUSE: 0x62
Writing fuse value 62 to ATtiny...
Writing complete.

Write HFUSE: 0xDF
Writing fuse value DF to ATtiny...
Writing complete.

Write EFUSE: 0xFF
Writing fuse value FF to ATtiny...
Writing complete.

Fuses will be read again to check values...
Reading fuse settings from ATtiny...
  LFuse: 62, HFuse: DF, EFuse: FF
Reading fuse values complete.

Reading / programming finished, allow a new run.

or if no ATtiny is attached:

Reading signature from connected ATtiny...
Signature is: 0
Reading signature complete..

No valid ATtiny signature detected!
Try again.

Breadboard

This circuit uses an Arduino nano and an ebay DC-DC Step-Up Modul

Breadboard top view Breadboard back view

Revision History

Version 3.4

• Changed RAM to FLASH strings, which allows it to run on an ATmega168.

Version 3.3

• Additional erase if fuses are locked, fixed bug at lock printout, handle unattached button.
• Blink only 10 seconds after button operation.

Version 3.2

• Added lock bit readout

Version 3.0

• Added erase and read only commands

Version 2.2

• First public version