MightyOhm

Today I made a few improvements to the AVR HV Rescue Shield documentation, including screenshots of the Arduino sketch in action and a parts list in the assembly instructions.

Expect a FAQ and other stuff in the future as I get user feedback.

Rescue Shield says: Buy me!

Hackday posted the first image of the new Arduino MEGA platform, shown above.  According to Eliot, the MEGA features “12 PWM connections, 36 Digital I/O, and 16 analog inputs… 4 hardware UARTs and an I2C bus as well.”

Arduino MEGA – Hack a Day.

Have you created a project or hack based on the Asus WL-520gU or WL-500gP Wireless Routers?

It doesn’t matter if it was inspired by my project or developed independently – I’d love to hear from you!

I’m putting together a talk for NOTACON and I’d like to feature as many projects as I can to spread the word about how powerful, flexible, and affordable these routers are, especially when coupled with a Linux package (DD-WRT, Tomato, OpenWrt, etc.) and USB devices.

If you’d like to have your project included in the talk, leave a comment or contact me directly.

This all started last year, when I was playing with an ATmega168 microcontroller and did something silly.  I programmed the RSTDISBL fuse bit, which effectively makes it impossible to reflash the chip using an ordinary (serial) programmer.

Instead of giving up and throwing out the “dead” chip,  I decided to try to revive it using an obscure high voltage parallel programming mode that isn’t supported by most AVR programmers.  Armed with my Arduino and the ATmega168 datasheet, I quickly designed and constructed a programmer using parts I already had on my workbench.

A few hours later, I tested my new programmer and it worked!  I revived my “dead” AVR by using spare parts and a few lines of Arduino code.  That week I published the schematics and Arduino sketch to the site and called it my Arduino-based AVR High Voltage Programmer.

The response was overwhelming.  Since I first posted the design, many people have built their own and used it to fix their “dead” AVR microcontrollers by restoring the fuse bits to sane values.  I even received several requests for a PCB and/or kit based on the design, which got me thinking…

Today I’m proud to introduce:

The AVR HV Rescue Shield

The AVR HV Rescue Shield is a high voltage parallel mode fuse programmer for Atmel AVR microcontrollers.

It currently supports the ATmega48/88/168/328 series and the ATtiny2313.  The Rescue Shield does everything my original AVR High Voltage Programmer does, and a lot more.  I think the new features make this a really useful tool for anyone working with AVR microcontrollers.

New features include:

• Custom 2-layer PCB with silkscreen and soldermask.  No more hacking and modifying perfboards to fit Arduino’s nonstandard pin spacing!
• Onboard 12V DC-DC boost converter eliminates the need for an external 12V power supply
• Support for two of the most common families of AVR microcontrollers, the ATmega48/88/168 and ATtiny2313
• Support for programming the extended fuse (EFUSE) byte.
• A new interactive mode, where desired fuses can be entered using the Arduino’s serial port.
• Separate Ready and Burn indicators
• Protection resistors on every single data, control, and supply line to the target AVR, meaning that your Arduino and AVR should survive any mishaps during programming, including inserting the AVR backwards or off by 1 pin.

I spent considerable time testing each new feature and documenting the Arduino sketch.  I hope that you’ll find that the finished product was worth the wait!

Ordering instructions:

To purchase bare PCBs and kits, head over to the AVR HV Rescue Shield product page.

Make:SF‘s monthly San Francisco meeting is tonight at 6:30PM at Instructables HQ on 489 Clementina St.

More details here and here.

Disclosure: I’m leading the meeting tonight, taking over for our usual host Andrew Milmoe.

Come and check out Make:SF!