PWM

4G LTE Module PWM Channel Mapping

Note

PWM Channel 1 on RDA8910 and RDA8955 based modules has limited configurable period and duty cycle.

PWM Channel	EC600U	EC200U	N58	N716	L610	EG915U
PWM CH 0	Pin 70	Pin 135	Pin 39	Pin 38	Pin 135	Pin 20
PWM CH 1	Pin 54	Pin 5	–	Pin 67	Pin 5	Pin 21

GSM/NB-IoT Module PWM Channel Mapping

RDA8955 based modules

PWM Channel	M590 Pin	MC65 Pin	A9 Pin
PWM CH 0	Pin 58	Pin 25	Pin 50
PWM CH 1	Pin 59	Pin 24	Pin 49

MT2503/MT6261/MT2625 based modules

PWM Channel	M56 Pin	MC60 Pin MC20(U) Pin	M66 Pin	BC20 Pin	SIM868 Pin
PWM CH 0	Pin 12	Pin 47	Pin 16	Pin 47	Pin 6
PWM CH 1	Pin 27	Pin 28	–	Pin 3	Pin 57
PWM CH 2	–	–	–	Pin 36	–
PWM CH 4	–	–	–	Pin 61	–

Example Usage

#include <hw/pwm.h>

/* Init PWM */
pwm_init(PWM_CH0);

/* configure PWM @ 1Khz 50% duty */
pwm_config(PWM_CH0, 1000, 50);

/* start pwm */
pwm_start(PWM_CH0);

/* stop PWM */
pwm_stop(PWM_CH0);

/* free PWM */
pwm_free(PWM_CH0);

Application Example

waybyte/example-pwm

API Reference

Header File

Source: include/hw/pwm.h

#include <hw/pwm.h>

Functions

int pwm_init(int ch)

Initialize PWM channel and setup pin-muxing. This function must be called before calling any other PWM function.

Parameters:: ch – PWM Channel pwmch_e
Returns:: 0 on success, negative value on error

int pwm_config(int ch, unsigned int freq, unsigned int cycle)

Configure PWM channel parameters

Parameters:

ch – PWM Channel to configure pwmch_e
freq – PWM Frequency to set
cycle – PWM Duty cycle

Returns:

0 on success, negative value on error

int pwm_start(int ch)

Start PWM output

Parameters:: ch – PWM Channel to start pwmch_e
Returns:: 0 on success, negative value on error

int pwm_stop(int ch)

Stop PWM output

Parameters:: ch – PWM Channel to stop pwmch_e
Returns:: 0 on success, negative value on error

int pwm_free(int ch)

Release PWM channel and IO function changed to GPIO

Parameters:: ch – PWM Channel to free pwmch_e
Returns:: 0 on success, negative value on error

Note

Please refer header file for actual number of channels available for respective board.

Header File

Source: include/plat/def_pwm.h

#include <plat/def_pwm.h>

Enumerations

enum pwm1_prd_e

PWM Channel 1 - Fixed Period in milliseconds

Note

Only for Platform with RDA8910 SoC

Values:

enumerator PWM1_PRD_125MS

enumerator PWM1_PRD_250MS

enumerator PWM1_PRD_500MS

enumerator PWM1_PRD_1000MS

enumerator PWM1_PRD_1500MS

enumerator PWM1_PRD_2000MS

enumerator PWM1_PRD_2500MS

enumerator PWM1_PRD_3000MS

enum pwm1_duty_e

PWM Channel 1 - Fixed On-time/Duty cycle in milliseconds

Note

Only for Platform with RDA8910 or RDA8955 SoC

Values:

enumerator PWM1_DUTY_UNDEFINE

enumerator PWM1_DUTY_15_6MS

enumerator PWM1_DUTY_31_2MS

enumerator PWM1_DUTY_46_9MS

enumerator PWM1_DUTY_62_5MS

enumerator PWM1_DUTY_78_1MS

enumerator PWM1_DUTY_93_7MS

enumerator PWM1_DUTY_110MS

enumerator PWM1_DUTY_125MS

enumerator PWM1_DUTY_141MS

enumerator PWM1_DUTY_156MS

enumerator PWM1_DUTY_172MS

enumerator PWM1_DUTY_187MS

enumerator PWM1_DUTY_203MS

enumerator PWM1_DUTY_219MS

enumerator PWM1_DUTY_234MS

enum pwmch_e

PWM Channels

Values:

enumerator PWM_CH0: PWM Channel 0 - Pin 47

enumerator PWM_CH1: PWM Channel 1 - Pin 3

enumerator PWM_CH2: PWM Channel 2 - Pin 36

enumerator PWM_CH3: PWM Channel 3 - Pin 61