The Pwm_input driver can't work at v1.13.0-alpha

PX4 Autopilot Drivers & Sensors 🔧
1

I use the latest master v1.13.0-alpha firmware.which’s Pam_input driver can’t work like before. It fails with the message:

pwm_input start
INFO [pwm_input] timer/channel alloc failed (-16 -16)

here is my firmware’s version message:
NuttShell (NSH) NuttX-10.2.0
nsh> ver all
HW arch: PX4_FMU_V5
HW type: V550 HW version: 0x00000005
HW revision: 0x00000000
FW git-hash: ed28b216c7f904c2e2f95cd494fa1b0c82e6f4e0 FW version: 1.13.0 40 (17629248)
FW git-branch: master
OS: NuttX
OS version: Release 8.2.0 (134349055)
OS git-hash: 0a5f0d0b6cd238ad824c594cf1183ed8d99daaff Build datetime: Feb 2 2022 17:03:55
Build uri: localhost
Build variant: default
Toolchain: GNU GCC, 9.3.1 20200408 (release) PX4GUID: 000200000000333039313538510a00320036
MCU: STM32F76xxx, rev. Z

2

I am getting the exact error.

nsh> pwm_input start
ERROR [pwm_input] timer/channel alloc failed (-16 -16)

Were you able to find a solution? Is it fixed yet?

3

You might want to create a new thread instead of necrobumping this 2 year old post, and then give proper info about your hardware and software versions, things you tried, context, etc.

4

Solved!
pwm_input driver must begin before pwm_out driver.

pwm_out driver allocates all available gpio ports and pwm_input cannot allocate its dedicated gpio a second time.

By editing rc.sensors file in the px4 source code, when the correct parameters are turned on the pwm_input driver starts at boot before pwm_out.

Example rc.sensors addition.

if param compare SENS_EN_CUSTOM 1
then
	pwm_input start
	custom_driver start
fi