Comments on: Working with 7 Segment Display and Raspberry PI Computer Boards with Python (1 Digit and 4 Digit)

By: Franz Fakler

Franz Fakler — Wed, 26 Oct 2022 10:03:52 +0000

Thank You for the response. I use such a GPIO Adapter … (with Raspberry 3)
https://www.openimpulse.com/blog/products-page/product-category/2-pcs-gpio-adapter-raspberry-pi-v3-model-b-t-shape/
There were two reasons why it did not work :
a) I always look at the physical PIN for the connections with the Dupont cable. The numbers on the breadboard are not perfectly aligned with the numbers on the GPIO adapter … so one connection was bad.
b) The resistors did loose the contact with the breadboard

By: peppe8o

peppe8o — Tue, 25 Oct 2022 17:02:20 +0000

In reply to Franz Fakler.

Hi Franz,
if only one segment is not working (Display Ph. 1 -> BCM 9 -> RPI Ph 21), then there must be a wiring problem. It may be:
– a failing soldering on RPI -> you can try changing the Raspberry PI port for the segment 1
– a failing wire -> you can try changing the wire
– a failing resistor -> you can try changing the resistor
– a failing breadboard line -> you can try changing the display position in your breadboard
– a failing display PIN -> you can try connecting the display PIN 1 to the 3,3V port on Raspberry PI via the resistor

In the code, the command “10” performs the “GPIO.cleanup()”, which clears all the Raspberry PI GPIOs status (put them to zero), so shutting down the whole display. WHat is not working in this?

By: Franz Fakler

Franz Fakler — Tue, 25 Oct 2022 14:43:24 +0000

Hello ! One segment is NOT working.

E segment is not working

=Display Pin 1
=Raspb physical : pin 21
= BCM GPIO 9
that means numbers 8 6 0 2 do not show up

In the code I cannot find this instruction :
10 (OFF) -> [0,0,0,0,0,0,0]

Cleanup is not working either …

# Display number in argument
if numDisplay == 10:
GPIO.cleanup()
else:
GPIO.output(display_list, arrSeg[numDisplay])
Any idea why ? Connections seem to be fine …