Four letter phat not working


I have followd all the instructions to install the device. If I try to run the code in Thonny it gives me this.

Traceback (most recent call last):
File “/home/pi/Pimoroni/fourletterphat/examples/tests/”, line 10, in
File “/usr/lib/python3/dist-packages/fourletterphat/”, line 125, in clear
File “/usr/lib/python3/dist-packages/fourletterphat/”, line 162, in setup
File “/usr/lib/python3/dist-packages/fourletterphat/”, line 57, in begin
self._device.write_i2c_block_data(self._i2c_addr, HT16K33_SYSTEM_SETUP | HT16K33_OSCILLATOR, [])
OSError: [Errno 121] Remote I/O error

I would be very glad if you could help me get it to run.


run sudo i2cdetect -y 1 and see if its detected. it’s i2c address is 70


.i had no issues running mine first time ,but i used Python3,did you try it with Python,not saying it will matter but who know,it might


Remote IO error is usually an i2c error. From my experience anyway.
You have a point though. I have some code that crashes in python 2 but not in python 3 , and vise versa. A lot of the time it depends on the install command you used. setup python or setup python3 etc.


Thank you for your feed back. Silly me, I thougt I could get it running with out soldering! Now i soderd it (with Led, I jused a mask, hop it protected me.) and it works! Haleluia!


You’d need prolonged exposure to the fumes for it to ever harm you. I use Standard 60/40 formula rosin core solder. No mask, I just do it in a well ventilated area and try not to breath the fumes.