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Diffstat (limited to 'bsps/arm/beagle/include/bsp/bbb-pwm.h')
| -rw-r--r-- | bsps/arm/beagle/include/bsp/bbb-pwm.h | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/bsps/arm/beagle/include/bsp/bbb-pwm.h b/bsps/arm/beagle/include/bsp/bbb-pwm.h new file mode 100644 index 0000000000..cf5d6fe552 --- /dev/null +++ b/bsps/arm/beagle/include/bsp/bbb-pwm.h @@ -0,0 +1,178 @@ +/** + * @file + * + * @ingroup arm_beagle + * + * @brief BeagleBone Black PWM support definitions. + */ + +/** + * Copyright (c) 2016 Punit Vara <punitvara@gmail.com> + * + * The license and distribution terms for this file may be + * found in the file LICENSE in this distribution or at + * http://www.rtems.org/license/LICENSE. + */ + +/** Some constants are taken from + * https://github.com/VegetableAvenger/BBBIOlib/blob/master/BBBio_lib/BBBiolib_PWMSS.h + */ + +#ifndef LIBBSP_ARM_BEAGLE_BBB_PWM_H +#define LIBBSP_ARM_BEAGLE_BBB_PWM_H + +#ifdef __cplusplus +extern "C" { +#endif /* __cplusplus */ + +/** + * @brief BeagleBone Black PWM Macros. + */ +#define BBB_CONTROL_CONF_GPMC_AD(n) (0x800 + (n * 4)) +#define BBB_CONTROL_CONF_LCD_DATA(n) (0x8a0 + (n * 4)) + +/** + * @brief The set of possible PWM subsystem module + * + * Enumerated type to define various instance of pwm module. + */ +typedef enum{ + BBB_PWMSS0 = 0, + BBB_PWMSS1, + BBB_PWMSS2, + BBB_PWMSS_COUNT +}BBB_PWMSS; + +typedef enum{ + BBB_P8_13_2B = 3, + BBB_P8_19_2A, + BBB_P8_45_2A, + BBB_P8_46_2B, + BBB_P8_34_1B, + BBB_P8_36_1A, + BBB_P9_14_1A, + BBB_P9_16_1B, + BBB_P9_21_0B, + BBB_P9_22_0A, + BBB_P9_29_0B, + BBB_P9_31_0A +}bbb_pwm_pin_t; + +#define BBB_P8_13_MUX_PWM 4 +#define BBB_P8_19_MUX_PWM 4 +#define BBB_P8_45_MUX_PWM 3 +#define BBB_P8_46_MUX_PWM 3 +#define BBB_P8_34_MUX_PWM 2 +#define BBB_P8_36_MUX_PWM 2 +#define BBB_P9_14_MUX_PWM 6 +#define BBB_P9_16_MUX_PWM 6 +#define BBB_P9_21_MUX_PWM 3 +#define BBB_P9_22_MUX_PWM 3 +#define BBB_P9_29_MUX_PWM 1 +#define BBB_P9_31_MUX_PWM 1 +#define BBB_PWM_FREQ_THRESHOLD 0.5f + +/** + * @brief BeagleBone Black PWM API. + */ + +/** + * @brief This function intilizes clock for pwm sub system. + * + * @param PWMSS_ID It is the instance number of EPWM of pwm sub system. + * + * @return true if successful + * @return false if not successful + * + **/ +bool beagle_pwm_init(BBB_PWMSS pwmss_id); + +/* PWMSS setting + * set pulse argument of epwm module + * + * @param pwm_id : EPWMSS number , 0~2 + * @param pwm_freq : frequency to be generated + * @param dutyA : Duty Cycle(in percentage) in PWM channel A + * @param dutyB : Duty Cycle(in percentage) in PWM channel B + * + * @return : 1 for success + * @return : 0 for failed + * + * @example : beagle_pwm_configure(0 , 50.0f , 50.0f , 25.0f); // Generate 50HZ pwm in PWM0 , + * // duty cycle is 50% for ePWM0A , 25% for ePWM0B + * + * @Note : + * find an number nearst 65535 for TBPRD , to improve duty precision, + * + * Using big TBPRD can increase the range of CMPA and CMPB , + * and it means we can get better precision on duty cycle. + * + * EX : 20.25% duty cycle + * on TBPRD = 62500 , CMPA = 12656.25 ( .25 rejection) , real duty : 20.2496% (12656 /62500) + * on TBPRD = 6250 , CMPA = 1265.625 ( .625 rejection), real duty : 20.24% (1265 6250) + * on TBPRD = 500 , CMPA = 101.25 ( .25 rejection) , real duty : 20.2% (101/500) + * + * Divisor = CLKDIV * HSPCLKDIV + * 1 TBPRD : 10 ns (default) + * 65535 TBPRD : 655350 ns + * 65535 TBPRD : 655350 * Divisor ns = X TBPRD : Cycle + * + * accrooding to that , we must find a Divisor value , let X nearest 65535 . + * so , Divisor must Nearest Cycle/655350 + */ +int beagle_pwm_configure(BBB_PWMSS pwm_id, float pwm_freq, float duty_a, float duty_b); + +/** + * @brief This API enables the particular PWM module. + * + * @param pwmid It is the instance number of EPWM of pwm sub system. + * + * @return true if successful + * @return false if fail + * + **/ +bool beagle_pwm_enable(BBB_PWMSS pwmid); + +/** + * @brief This API disables the particular PWM module. + * + * @param pwmid It is the instance number of EPWM of pwm sub system. + * + * @return true if successful + * @return false if fail + * + **/ +bool beagle_pwm_disable(BBB_PWMSS pwmid); + +/** + * @brief This function enables pinmuxing for PWM module. + * + * @param pin_no It is individual pin at which freuqency need to be generated. + * It should be according to pwm sub system. + * + * @param pwm_id It is the instance number of EPWM of pwmsubsystem. + * + * @return true if successful + * @return false if fail + * + **/ +bool beagle_pwm_pinmux_setup(bbb_pwm_pin_t pin_no, BBB_PWMSS pwm_id); + +/** + * @brief This function determines whether PWMSS-wide clocks enabled or not. + * + * @param pwmss_id It is the instance number of PWMSS which clocks need to be + * checked. + * + * @return true if successful + * @return false if fail + * + **/ +bool beagle_pwmss_is_running(unsigned int pwmss_id); + + +#ifdef __cplusplus +} +#endif /* __cplusplus */ + +#endif /* LIBBSP_ARM_BEAGLE_BBB_PWM_H */ |