/* * Copyright (C) 2014 Freie Universität Berlin * * This file is subject to the terms and conditions of the GNU Lesser General * Public License v2.1. See the file LICENSE in the top level directory for more * details. */ /** * @ingroup lpc2387 * @{ * * @file * @brief CPU specific low-level PWM driver implementation for the LPC2387 * * @author Hauke Petersen * * @} */ #include "bitarithm.h" #include "lpc2387.h" #include "periph/pwm.h" #include "periph_conf.h" /* guard file in case no PWM device is defined */ #if PWM_NUMOF #define PCPWM1 BIT6 /** * @note The PWM is always initialized with left-aligned mode. * * TODO: add center and right aligned modes */ int pwm_init(pwm_t dev, pwm_mode_t mode, unsigned int frequency, unsigned int resolution) { (void) mode; /* unused */ switch (dev) { #if PWM_0_EN case PWM_0: /* select function PWM[3] for pins */ PWM_0_PORT &= ~((3 << PWM_0_CH0_PIN * 2) | (3 << PWM_0_CH1_PIN * 2) | (3 << PWM_0_CH2_PIN * 2)); PWM_0_PORT |= (PWM_0_FUNC << PWM_0_CH0_PIN * 2) | (PWM_0_FUNC << PWM_0_CH1_PIN * 2) | (PWM_0_FUNC << PWM_0_CH2_PIN * 2); /* power on PWM1 */ pwm_poweron(dev); /* select PWM1 clock */ PCLKSEL0 &= ~(BIT13); PCLKSEL0 |= (BIT12); /* reset PWM1s counter */ PWM1TCR = BIT1; /* set prescaler */ PWM1PR = (F_CPU / (frequency * resolution)) - 1; /* set match register */ PWM1MR0 = resolution; PWM_0_CH0_MR = 0; PWM_0_CH1_MR = 0; PWM_0_CH2_MR = 0; /* reset timer counter on MR0 match */ PWM1MCR = BIT1; /* enable PWM1 channel 3, 4 and 5 */ PWM1PCR = (1 << (8 + PWM_0_CH0)) | (1 << (8 + PWM_0_CH1)) | (1 << (8 + PWM_0_CH2)); /* enable PWM1 timer in PWM mode */ PWM1TCR = BIT0 + BIT3; /* update match registers */ PWM1LER = BIT0 | (1 << PWM_0_CH0) | (1 << PWM_0_CH1) | (1 << PWM_0_CH2); break; #endif } return 0; } int pwm_set(pwm_t dev, int channel, unsigned int value) { switch (dev) { #if PWM_0_EN case PWM_0: switch (channel) { case 0: PWM_0_CH0_MR = value; PWM1LER |= (1 << PWM_0_CH0); break; case 1: PWM_0_CH1_MR = value; PWM1LER |= (1 << PWM_0_CH1); break; case 2: PWM_0_CH2_MR = value; PWM1LER |= (1 << PWM_0_CH2); break; default: return -2; break; } break; #endif } return 0; } void pwm_start(pwm_t dev) { switch (dev) { #if PWM_0_EN case PWM_0: PWM1TCR |= BIT0; break; #endif } } void pwm_stop(pwm_t dev) { switch (dev) { #if PWM_0_EN case PWM_0: PWM1TCR &= ~(BIT0); break; #endif } } void pwm_poweron(pwm_t dev) { switch (dev) { #if PWM_0_EN case PWM_0: PCONP |= PCPWM1; break; #endif } } void pwm_poweroff(pwm_t dev) { switch (dev) { #if PWM_0_EN case PWM_0: PCONP &= ~(PCPWM1); break; #endif } } #endif /* PWM_NUMOF */