Hi,
I build my image according to the documentation, but unfortunately the /sys/class/gpio/gpio430/ is not populated at all, so i can’t acces the physical pins.
I also created the issue
Any ideas what should be done. Thank yo in advance
1 Like
Hi qczek,
I just tried to reproduce on my Duo256M with Buildroot image. For GP10 / 430 I get the following error:
[root@milkv-duo]~# echo 430 > /sys/class/gpio/export
sh: write error: Resource busy
I am not sure why, but maybe the pin has been reserved for I2C-2 by the OS?
The other GPIOs work just fine, e.g. GP9 / 370
[root@milkv-duo]~# duo-pinmux -w GP9/GP9
[root@milkv-duo]~# echo 370 > /sys/class/gpio/export
[root@milkv-duo]~# echo out > /sys/class/gpio/gpio370/direction
[root@milkv-duo]~# echo 1 > /sys/class/gpio/gpio370/value
[root@milkv-duo]~# echo 0 > /sys/class/gpio/gpio370/value
Are you able to use other GPIOs for your project?
Notice that the target gpio won’t show up in /sys/class/gpio until it has been exported, e.g.
[root@milkv-duo]~# ls /sys/class/gpio/
export gpiochip384 gpiochip448 unexport
gpiochip352 gpiochip416 gpiochip480
[root@milkv-duo]~# echo 370 > /sys/class/gpio/export
[root@milkv-duo]~# ls /sys/class/gpio/
export gpiochip352 gpiochip416 gpiochip480
gpio370 gpiochip384 gpiochip448 unexport
1 Like
Hi, Thank you for your response. Just checked and the GP9/370 is working fine.
I’m not an expert, but it looks like the GPIO memory mapping is based on board definition files locate there:
The question is why there is no file for SG2002 chip (which is used for Duo256M), but only CV1800 related files…
Kris
PS,
Maybe the SDK V2 should be used
1 Like
Just checked with SDK V2, same problem
[root@milkv-duo]~# duo-pinmux -r GP10
GP10 function:
[ ] CV_4WTDO_CR_2WTMS
[ ] VI0_D_11
[ ] VO_D_2
[v] GP10
[ ] IIC2_SDA
[ ] PWM_10
[ ] SPI0_SDO
[ ] DBG_14
register: 0x30011ac
value: 3
[root@milkv-duo]~# echo 430 > /sys/class/gpio/export
sh: write error: Resource busy
[root@milkv-duo]~#
1 Like