Warning: Digispark uses Attiny85 PIN#1 as I/O - remove RESET button functionality
FOR ADVANCED USERS ONLY
Digispark inherits most of it's personallity from the littlewire project, http://littlewire.cc/ and having been around longer there is a significant following of users. In addition to a pedigree heritage, there is a ready set of libraries available for the Digispark. I have used several with the Trinket without modifications with perfect success. So, with the bootloader of the Digispark a weebit smaller and the availability of a simple-to-use uploader program, micronucleus.exe (Windows,) I figured I should do a little Frankenstein doctoring and flash the Trinket hardware with the Digispark bootloader software. The results is excellent (or, said properly, my results were excellent.)
micronucleus CompiledFileName.hex" and you then plug in the Digispark after-the-fact! Micronucleus is polling for the connection so there is a 60 second window ... an eternity if you have been trying to hit the Trinket timing. Simply download
micronucleus.exeand store it somewhere in your path, I put mine with my other Arduino stuff here:
C:\ProgramFiles\arduino_105\hardware\tools\avr\binand then you can open a command window to your OS, CD to the Arduino GUI temporary directory and upload the HEX. This is not even painful and I have tested it on Win-Vista 32-bit with Arduino 1.0.5 without issue. Of course, the standard disclaimer of your results may differ is appropriate.
- You MUST install the Digispark boards.txt file and core files, just like the Trinket. When this is successful, you will see the 4 Digispark entries under Arduino - Tools - Boards. You must compile with a Digispark board selected, not Trinket.
- Core Files are here: https://github.com/digistump/DigisparkArduinoIntegration/tree/master/hardware/digispark
- USB drivers, See step #3: http://www.instructables.com/id/Digispark-DIY-The-smallest-USB-Arduino/
- There is NO need to compile and upload... simply do a Verify (check mark) in the GUI. If you have your Arduino Preferences set to Show Verbose Output during compilation, then you will see the path in the console window.
- To upload, type: micronucleus fade.cpp.hex
Overview of proceduresCaveat Emptor
This is a one-way street. Installation of the Digispark firmware and appropriate fuse settings will prevent you from re-flashing the converted Trinket back to an un-converted Trinket UNLESS you have a HV-programmer. /endofitoldyouso
I wrote a piece for Adafruit back in 4Q13 on how to assist in reflashing the Trinket firmware. The piece is here:
A very similar procedure using the Jig can be accomplished for the Exorcism... er, Trinket --> Digispark conversion.
The Digispark firmware is: