Faq - adafruit learning system Trinket Introduction Manual

FAQ

I can't seem to upload to my Trinket when it's plugged into a USB 3.0 port (newer
Macbooks have USB 3 ports)
Trinket's bootloader is finicky about USB 3 ports, and might not work on them. Try
connecting to any USB 2 ports you have or go through a USB 1 or USB 2 hub (nearly all
hubs are v2 or v1 instead of v3)
When uploading with the Arduino IDE, I get a lot of "(expected 4, got -5)" warnings and
then "avrdude: verification error; content mismatch"
Check that you followed the instructions for updating the Arduino IDE, including replacing
the old avrdude.conf
Hmm I'm still having problems with Arduino/Avrdude - and I definitely did the required
updates
One fix that works for some people is to edit avrdude.co nf and set the
chip_erase_delay = 900000;
under the ATtiny85 heading to
chip_erase_delay = 400000;
That is, a shorter delay.
Can Trinket driver Neopixels (strips, squares, etc)? How many?
Yes! Trinket was designed to drive short segments of NeoPixels. There is enough RAM
on the attiny85 to drive 100 pixels, but depending on program RAM usage you may have
to scale back to 60 or 40.
Yo u can use EITHER the 3V o r 5V Trinket, at EITHER 8 o r 16MHz!
To use with neopixels:
1. Connect the + power line of the strip to VBUS (5V from USB), to VBAT if you are
powering the Trinket with 4-7VDC, or to a separate 4-7VDC power source such as a
3 or 4 pack of AA batteries.
2. Connect the - common ground to the battery pack (if being used) and also to the
Trinket GND pin
3. Connect the data in line to Trinket #1 - this will let you also see when data is being
sent because the #1 red LED will flicker. You can use other pins but start with #1
since its easiest to debug and use
4. Install the NeoPixel library as detailed in our Uber Guide
change the PIN to 1 (its 6 by default)
5. Upload and enjoy!
Can the Trinket drive your Adafruit I2C LED Backpacks for 7-segment/matrix displays?
© Adafruit
Industries
(http://adafru.it/cEY)- this step is not optional!
https://learn.adafruit.com/introducing-trinket
(http://adafru.it/cEz), and
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