Scroll pHat & test-all.py example


#1

I have a Pi Zero to which I soldered some GPIO header pins.
I bought the Scroll pHat and soldered to GPIO pin connector block.
To test it out I am running the example python program “test-all.py”.

The LED’s light up and then go off as expected from reading the code.
However I get a lot of “IO error” messages.
Is this to be expected or is it a sign of errors in my soldering?


#2

I don’t get any errors. Does it say anything other than “IO Error” ?

What about the other examples? (note, if you’re using the latest version of the code from the Pimoroni github repository then many of the examples don’t currently work unless you copy the font.png file from the library folder into the examples folder, hopefully this will be fixed soon)


#3

GbCould you post the errors you receive and when they occur?

… but yes, the repo was broken at the start of the week (blame me). If you have installed the scrollphat lib by hand, I recommend using the one line installer at this point, which will copy everything where it should, hopefully:

curl -sS get.pimoroni.com/scrollphat | bash

#4

Gisky: It would appear the “IO error” message originates from the caught “IOError” exception in the function scrollphat.update().

Adding extra print statements to the “test-all.py” script hasn’t so far identified under what condition the error arises as it randomly appears either when an LED is set or reset.


#5

It could be flaky soldering ( I’ve seen a few people have problems with pins on their Zero even with apparently great soldering that have been fixed with a touch up ) or it could be something else.

We’ll do some investigation this end when we get some time, to see if there’s any way to reduce the error rate. Otherwise we’ll just squash it in code. It sounds bad, but in practice you can just fire out updates to the driver chip constantly and it’s irrelevant if there are failures- as long as they’re not consistent.