ATTINY Fuse Repair Programmer/Fuse Doctor V3.4

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ATtiny Fuse Repair Programmer V2.0 — High Voltage Serial Fuse Recovery Tool with Advanced Mode

Recover Bricked ATtiny Devices in Seconds — No Computer Required!

The ATtiny Fuse Repair Programmer is a standalone AVR High Voltage Serial Programmer designed to restore Microchip ATtiny devices fuse settings, regardless of their current state.

Accidentally programmed the RSTDISBL fuse?

Disabled the SPIEN fuse?

Configured the wrong CKSEL clock fuse values?

Programmed the Debug Wire Enable Fuse?

No problem.

Simply insert a supported ATtiny device in the correct socket, connect power, and within seconds the programmer restores the fuses back to their factory default settings.

LED indicators provide instant feedback:

Green LED: Programming successful

Yellow LED: Programming error

No computer, software installation, USB drivers, or complicated setup required. Please watch the video here.

Standalone Mode + Advanced Terminal Mode

This version includes all the features of the standard ATtiny Fuse Repair Programmer V2.0, plus an advanced terminal mode.

You can use it in two ways:

Standalone Mode

Use the programmer without a computer:

Insert the ATtiny device.

Apply the required power.

The programmer automatically restores the fuse settings.

Check the LED status.

Advanced Mode

Connect the programmer to a PC terminal using either:

USB-to-TTL interface, or

RS232 interface

(Interface adapter not included.)

Advanced mode provides additional diagnostic and programming features.

Advanced Mode Features

1. Read Fuse Values From a Bricked Device

Ever wondered what fuse settings caused your ATtiny device to become unusable?

Advanced mode allows you to read the current fuse values and display the results in a terminal program.

2. Program Custom Fuse Values

Advanced mode allows you to manually enter custom 8-bit fuse values.

The programmer will write those fuse values to any supported device.

3. Disable Signature Verification

If your device supports High Voltage Serial Programming but is not included in the standard device list, advanced mode provides an option to disable signature verification. This allows fuse programming even when the device signature bytes are corrupted.

Preserve Your Flash and EEPROM Contents

A unique feature of this programmer is the ability to restore fuse settings while preserving your existing firmware.

To preserve Flash and EEPROM:

Install jumper J1

Perform the fuse restore operation

The erase command will be skipped, allowing your program memory and EEPROM contents to remain intact.

Important: If lock bits have been programmed, the device must be erased before fuse restoration can succeed. In this case, J1 must not be installed, and Flash/EEPROM contents will be erased.

Why Was This Created?

It is surprisingly easy to permanently disable normal programming on AVR devices while experimenting with fuse settings.

Years ago, while developing AVR firmware, I was making great progress and was excited to test new code. During programming, something went wrong and I accidentally locked myself out of my last device.

After repeatedly losing devices and waiting days or weeks for replacements, I decided to design a simple standalone recovery tool.

The goal was straightforward:

1. No computer required
2. No USB drivers
3. No complicated software
4. Fast recovery in seconds
5. 
   

The first version was designed and built from the ground up. Over time, the design evolved and gained additional features based on real-world use.

What Makes This Programmer Different?

Many programming tools require a computer and specialized software. This programmer is designed specifically for recovering ATtiny devices quickly and reliably.

Features include:

1. Standalone fuse recovery
2. Advanced fuse diagnostics
3. Custom fuse programming
4. Flash/EEPROM preservation option
5. High Voltage Serial Fuse Programming capability
6. Direct support from the original designer

Power Requirements

For reliable operation, use:

DC power supply greater than 14.5V

Positive center polarity

The power supply is not included to reduce cost and shipping weight.

It is recommended to verify your power supply voltage and polarity with a voltmeter before use.

Important Notes

Only supported ATtiny devices listed in the device list below can be programmed in normal mode.

If lock bits are programmed, an erase operation will be required.

Please read the complete user guide before using the programmer.

Technical Support Included

You are purchasing directly from the original designer, not a reseller. If you have questions or encounter difficult devices, you will receive direct email support. I provide honest answers and will do my best to help you successfully recover and program your AVR devices.

After recovery, your ATtiny device can be programmed again using your preferred ISP programmer and software.

Never worry about accidentally bricking your AVR devices again!

Supported Devices List:

All International Orders will be shipped on Fridays as long as the order is received by Friday at 9 AM Eastern time.