Microdot Phat I/O Error


Can anyone suggest what might be causing this error when I try any of the examples shipped with the Microdot Python library:

`pi@raspberrypi:~/Pimoroni/microdotphat/examples $ ./flash.pyTraceback (most recent call last):

File “./flash.py”, line 5, in
from microdotphat import clear, show, set_decimal, set_pixel, WIDTH, HEIGHT
File “/usr/lib/python2.7/dist-packages/microdotphat/init.py”, line 24, in
_n1 = NanoMatrix(address=0x63)
File “/usr/lib/python2.7/dist-packages/microdotphat/matrix.py”, line 63, in init
self.bus.write_byte_data(self.address, CMD_MODE, MODE)
IOError: [Errno 5] Input/output error

I also ran i2cdetect which showed no devices detected.

This as running the board on a Pi Zero which has been updated to Pixel. My Scroll Phat runs OK on this Pi.




most likely the contacts provided by your soldering job is flaky. Check the 2x3 leftmost pins (when header is at the top, matrices facing up) are OK.


Yes, that was it.