davembg

It actually wasn't 100k, it was 220ohm - so, that wasn't the issue. After additional testing, I found that SOME of the pins to respond. I'll post a list when my testing is completed.

No, it's 100k - the LED lights when connected to both 5v and 3.3v pins. Are you thinking the GPIO current isn't high enough with that 100k resistor? 'cause that's what I'm thinking..... The spec says the GPIO "HIGH" values are 3.3v, but, who knows. I'll drop the value the 330ohm and see if it's working.

Overall, the OS is quite good. I got an oled i2c display working using the luma.oled library and it gave me no grief whatsoever. Installed a 16GB eMMC module and dd'ed the armbian image and it booted just fine. The firefly image is a shit-show, I build it and was not impressed. Like you say, Armbian is a community supported project, so, I thought I'd direct my efforts here instead of a single-board fork. That said, they do provide some firefly specific code for gpio, I'll investigate that. Here is the armbianmonitor output link: http://ix.io/1oiz thanks for replying,

using latest Armbian: Linux indi 4.4.156-rockchip64 #21 SMP Wed Sep 19 13:14:57 CEST 2018 aarch64 aarch64 aarch64 GNU/Linux I can do the following (as sudo su), but, no voltage on the specified pin (pin 5, Linux pin 4): echo -n "4" > /sys/class/gpio/export echo -n "out" > /sys/class/gpio/gpio4/direction echo -n 1 > /sys/class/gpio/gpio4/value echo -n 0 > /sys/class/gpio/gpio4/value echo -n "4" > /sys/class/gpio/unexport I get no light on my generic LED with a 100k resistor - which lights when I move from pin 5 (Linux pin 4) MicroSD end of the board -> [ . . ] [ . . ] [ . . ] <- I'm connected here, pin on left is pin 5/4 (?) and pin 6 is GND Am I missing a kernel module? WiringOP and WiringPI libraries aren't working, gpiod (gpioset, gpiodetect, etc) not helping. This is the pin guide I'm using: https://docs.google.com/spreadsheets/d/1U3z0Gb8HUEfCIMkvqzmhMpJfzRqjPXq7mFLC-hvbKlE/edit#gid=0 Here is the output of cat /sys/kernel/debug/gpio: GPIOs 0-31, platform/pinctrl, gpio0: gpio-0 ( |vcc_host_5v ) out hi gpio-4 ( |sysfs ) out hi <---- this seems correct to me when /sys/class/gpio/gpio4/value is 1 gpio-30 ( |vcc_sd ) out hi GPIOs 32-63, platform/pinctrl, gpio1: gpio-50 ( |mdio-reset ) out hi gpio-58 ( |vcc_host1_5v ) out hi GPIOs 64-95, platform/pinctrl, gpio2: GPIOs 96-127, platform/pinctrl, gpio3: GPIOs 510-511, platform/rk8xx-gpio, rk8xx-gpio, can sleep: gpio-510 ( |? ) out hi gpio-511 ( |? ) out lo Any thoughts would be greatly appreciated, thx