GPIO pins not working

VisionFive 2 （English Forum)
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1

Hello!

I tried to run several Python GPIO example programs on my VisionFive 2. I connected the required components to VisionFIVE’s GPIO pins as instructed but they don’t work. Even simply making as LED blink doesn’t work! A LED turns on when connected to the 5V pin but that’s about it.

Is there a some kind of test program to run in order to check whether the GPIO pins work? Where should I start troubleshooting?

Firmware’s at the latest version and the OS is Debian.

2

not Python, just command line
I suppose you have read VisionFive2_40-Pin_GPIO_Header_UG.pdf
user guide
4.1. Configuring GPIO

  1. To configure GPIO, perform the following:
    Execute the following command to configure GPIO44:
    cd /sys/class/gpio
    echo 44 > export
  2. Locate to the GPIO44 directory:
    cd gpio44
    Note:
    In this command, 44 represents the Sys number of the pin. For more information, see GPIO Pinout (on page 9).
  3. Configure the direction of GPIO44 as in:
    echo in > direction
  4. Alternatively, configure the direction of GPIO44 as out:
    echo out > direction
  5. Configure the voltage level of GPIO44 as high:
    echo 1 > value
    Tip:
    You can use an oscilloscope to check the voltage level.
    or connect a current limited led
  6. Configure the voltage level of GPIO44 as low:
    echo 0 > value
    Tip:
    You can use an oscilloscope to check the voltage level.
  7. Connect the 3.3V Power pin with the GPIO44, and check the voltage level of GPIO44:
    cat value
  8. Connect the GND pin with the GPIO44, and check the voltage level of GPIO44:
    cat value
3

Some python application note for reference:

4

Tested GPIO44 with an oscilloscope and there’s certainly something happening. Here’s what happens after typing echo 1 > value: PXL-20241003-171055615-MP.jpg

And after typing echo 0 > value:
PXL-20241003-171045358-MP.jpg

5

Your cro is setup AC coupling, change it to DC
use 10X for higher impedance

I should have tested before posting,
but have now tested and it definitely works,
exactly as is in the StarFive documentation I posted.
Test setup - serial terminal, volt meter

first step setting up gpio44 on pin 40
cd /sys/class/gpio
echo 44 > export
cd gpio44
documentation missed a step, probably not good practice to drive the pin as output when connected to a voltage
echo in > direction
before applying an external voltage and reading pin value
using a jumper to 3v3
cat value
1
jumper to gnd
cat value
0
disconnect jumper
echo out > direction
echo 0 > value
cat value
0
volt meter 0v
echo 1 > value
cat value
1
volt meter 3v3

setting up a second pin
cd /sys/class/gpio
echo 60 > export
cd gpio60
now you can also work with gpio60 on pin 37

Now check your Python code