FriendlyELEC-Forum

Posted: **Sat Nov 19, 2016 9:41 pm**

This script is handy for testing header pins after soldering for me:

root@FriendlyARM:~# ./pintest 67
^C
root@FriendlyARM:~# cat pintest 
#!/bin/bash
echo $1 > /sys/class/gpio/export
echo out > /sys/class/gpio/gpio$1/direction
while (true)
do
echo 1 > /sys/class/gpio/gpio$1/value
sleep 1
echo 0 > /sys/class/gpio/gpio$1/value
sleep 1
done
root@FriendlyARM:~#

The argument is "Linux gpio" number from Neo Wiki (scroll down a bit):
http://wiki.friendlyarm.com/wiki/index.php/NanoPi_NEO#Layout

Unfortunately there is a typo bug in Wiki for pin 23, 93 is definitely not correct:

Code: Select all

root@FriendlyARM:~# ./pintest 93
./pintest: line 2: echo: write error: Invalid argument
./pintest: line 3: /sys/class/gpio/gpio93/direction: No such file or directory
./pintest: line 6: /sys/class/gpio/gpio93/value: No such file or directory
./pintest: line 8: /sys/class/gpio/gpio93/value: No such file or directory
./pintest: line 6: /sys/class/gpio/gpio93/value: No such file or directory
./pintest: line 8: /sys/class/gpio/gpio93/value: No such file or directory
./pintest: line 6: /sys/class/gpio/gpio93/value: No such file or directory
^C
root@FriendlyARM:~#

Hermann.

Posted: **Sun Nov 20, 2016 1:06 pm**

Testing revealed that 8 of the 2x12 pins I soldered first were bad.
After I fixed a problem with the soldering iron I did fix these pins.

And I soldered 12x1 and Debug Uart headers as well.
Since I wanted to connect an LCD display, I used a (shortened) row of 40 pin right-angled GPIO headers.
There are only 4 Debug Uart pins, so I had to remove 8 pins from that row before soldering.
In order to remove force from the soldering, I did use superglue to connect the black part of the row with Neo Air circuit board firmly before soldering the pins. See image below for the details:

With these headers FriendlyArm TFT LCD works with Neo Air without problems, see here:
http://www.friendlyarm.com/Forum/viewtopic.php?f=47&t=371&p=1141#p1141

Hermann.

FriendlyELEC-Forum

Testing pins after soldering headers to Neo

Testing pins after soldering headers to Neo

Re: Testing pins after soldering headers to Neo