RPi GPIO mapping for gpioctl

[aonishenko]

Hi!

I use RPi B (early release) and FreeBSD 11.1.
I use gpioctl to see GPIO pin states and I see, that GPIO pin 6 has OUT state and 1 on it value.

According to this - http://elinux.org/RPi_Low-level_peripherals#P1_Header_pinout.2C_top_row
GPIO 6 is the ground pin.

How it's possible? Or my gpioctl is wrong..

 

[Phishfry]

Your probably going to need a test led to figure out where FreeBSD maps the GPIO.

I usually start with the first GPIO pins after the RTC that I add.
So pins 1,3,5,7,9 for RTC module then for GPIO I start with PIN 11(GPIO17)

This GPIO pin is the same on all Pi boards.

Then for more GPIO I move down to next pin -PIN13, then PIN15 These are mapped to different GPIO locations depending on board.
https://www.raspberrypi-spy.co.uk/2012/06/simple-guide-to-the-rpi-gpio-header-and-pins/

Then skip the 3.3V power pin and move to next group of GPIO pins.

gpioctl is wrong..

Yes this is wrong. On early Pi notice there is no GPIO6. Do not confuse this with PIN6. They are not the same.

I would start with the odd numbered pins first. Pins 6,8,10 are for UART console.

 

[Phishfry]

Vadim's website is reallly useful.
https://vzaigrin.wordpress.com/2014/04/18/working-with-gpio-on-raspberry-pi-with-freebsd/