Thank you for update package regarding device tree overlays, the link is below.
I reviewed this according to the instruction on
Then I tried the kernel upgrade after update and upgrade, the instruction is,
Make sure that kernel is newer than 5.10.69-2-amlogic. If not, then try
$ sudo apt install -y linux-headers-5.10.69-3-amlogic-gacf75c74f9
$ sudo apt install -y linux-image-5.10.69-3-amlogic-gacf75c74f9
The result was,
E: Unable to locate package linux-headers-5.10.69-3-amlogic-gacf75c74f9
E: Couldn’t find any package by glob ‘linux-headers-5.10.69-3-amlogic-gacf75c74f9’
E: Couldn’t find any package by regex ‘linux-headers-5.10.69-3-amlogic-gacf75c74f9’
Consequently, I could not upgrade the kernel.
However, I tried to check 2ch PWM outputs following further instruction for uEnv.txt.
The pwmchip4 and 6 were added to /sys/class/pwm/pwmchip0 and pwmchip2.
I could see pwm0, pwm1 signals from pin 40, 18 separately after setting up period, duty_cycle and enable. Thanks.
But, two pwm signals were not generated at the same time.
It wonder I should wait for a kind of library like mraa or wiringpi.
Any advices would be greatly appreciated.