RIOT-OS/RIOT
RIOT-OS/RIOT
1
0
Fork 0
mirror of https://github.com/RIOT-OS/RIOT.git synced 2024-12-29 04:50:03 +01:00
Code Releases Activity

cpu/lpc2387: cleanup for the PWM driver

Browse Source
This commit is contained in:
Hauke Petersen 2016-12-13 16:44:36 +01:00
parent b24be6a6ae
commit 7b5d26340a
1 changed files with 78 additions and 113 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

191
cpu/lpc2387/periph/pwm.c
View File

@ -1,33 +1,33 @@
/* /*
* Copyright (C) 2014 Freie Universität Berlin * Copyright (C) 2014-2016 Freie Universität Berlin
* *
* This file is subject to the terms and conditions of the GNU Lesser General * This file is subject to the terms and conditions of the GNU Lesser
* Public License v2.1. See the file LICENSE in the top level directory for more * General Public License v2.1. See the file LICENSE in the top level
* details. * directory for more details.
*/ */
/** /**
* @ingroup lpc2387 * @ingroup cpu_lpc2387
* @{ * @{
* *
* @file * @file
* @brief CPU specific low-level PWM driver implementation for the LPC2387 * @brief CPU specific low-level PWM driver implementation for the LPC2387
* *
* The current implementation is somewhat limited: it supports only a single
* hardware PWM device (fixed to PWM1) and it is fixed on supporting 3 channels.
*
* @author Hauke Petersen <hauke.petersen@fu-berlin.de> * @author Hauke Petersen <hauke.petersen@fu-berlin.de>
* *
* @} * @}
*/ */
#include "cpu.h"
#include "assert.h"
#include "bitarithm.h" #include "bitarithm.h"
#include "lpc2387.h" #include "periph/pwm.h"
#include "periph_conf.h"
/* guard file in case no PWM device is defined */ /* guard file in case no PWM device is defined */
#if (PWM_0_EN || PWM_1_EN) #ifdef PWM_NUMOF
/* pull the PWM header inside the guards for now. Guards will be removed on
* adapting this driver implementation... */
#include "periph/pwm.h"
/** /**
* @note The PWM is always initialized with left-aligned mode. * @note The PWM is always initialized with left-aligned mode.
@ -36,135 +36,100 @@
*/ */
uint32_t pwm_init(pwm_t dev, pwm_mode_t mode, uint32_t freq, uint16_t res) uint32_t pwm_init(pwm_t dev, pwm_mode_t mode, uint32_t freq, uint16_t res)
{ {
(void) mode; /* unused */ if ((dev != PWM_DEV(0)) && (mode != PWM_LEFT)) {
return 0;
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 = (CLOCK_CORECLOCK / (freq * res)) - 1;
/* set match register */
PWM1MR0 = res;
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
default:
return 0;
} }
/* select function PWM[3] for pins */
PWM_PORT &= ~((3 << PWM_CH0_PIN * 2) |
(3 << PWM_CH1_PIN * 2) |
(3 << PWM_CH2_PIN * 2));
PWM_PORT |= (PWM_FUNC << PWM_CH0_PIN * 2) |
(PWM_FUNC << PWM_CH1_PIN * 2) |
(PWM_FUNC << PWM_CH2_PIN * 2);
/* power on PWM1 */
pwm_poweron(dev);
/* select PWM1 clock */
PCLKSEL0 &= ~(BIT13);
PCLKSEL0 |= (BIT12);
/* reset PWM1s counter */
PWM1TCR = BIT1;
/* set prescaler */
PWM1PR = (CLOCK_CORECLOCK / (freq * res)) - 1;
/* set match register */
PWM1MR0 = res;
PWM_CH0_MR = 0;
PWM_CH1_MR = 0;
PWM_CH2_MR = 0;
/* reset timer counter on MR0 match */
PWM1MCR = BIT1;
/* enable PWM1 channel 3, 4 and 5 */
PWM1PCR = (1 << (8 + PWM_CH0)) | (1 << (8 + PWM_CH1)) | (1 << (8 + PWM_CH2));
/* enable PWM1 timer in PWM mode */
PWM1TCR = BIT0 + BIT3;
/* update match registers */
PWM1LER = BIT0 | (1 << PWM_CH0) | (1 << PWM_CH1) | (1 << PWM_CH2);
return freq; return freq;
} }
uint8_t pwm_channels(pwm_t dev) uint8_t pwm_channels(pwm_t dev)
{ {
if (dev == PWM_0) { assert(dev == PWM_DEV(0));
return PWM_0_CHANNELS; return PWM_CHANNELS;
}
return 0;
} }
void pwm_set(pwm_t dev, uint8_t channel, uint16_t value) void pwm_set(pwm_t dev, uint8_t channel, uint16_t value)
{ {
switch (dev) { assert((dev == PWM_DEV(0)) && (channel < 3));
#if PWM_0_EN
case PWM_0: switch (channel) {
switch (channel) { case 0:
case 0: PWM_CH0_MR = value;
PWM_0_CH0_MR = value; PWM1LER |= (1 << PWM_CH0);
PWM1LER |= (1 << PWM_0_CH0); break;
break; case 1:
case 1: PWM_CH1_MR = value;
PWM_0_CH1_MR = value; PWM1LER |= (1 << PWM_CH1);
PWM1LER |= (1 << PWM_0_CH1); break;
break; case 2:
case 2: PWM_CH2_MR = value;
PWM_0_CH2_MR = value; PWM1LER |= (1 << PWM_CH2);
PWM1LER |= (1 << PWM_0_CH2);
break;
default:
return;
break;
}
break; break;
#endif
} }
} }
void pwm_start(pwm_t dev) void pwm_start(pwm_t dev)
{ {
switch (dev) { assert(dev == PWM_DEV(0));
#if PWM_0_EN PWM1TCR |= BIT0;
case PWM_0:
PWM1TCR |= BIT0;
break;
#endif
}
} }
void pwm_stop(pwm_t dev) void pwm_stop(pwm_t dev)
{ {
switch (dev) { assert(dev == PWM_DEV(0));
#if PWM_0_EN PWM1TCR &= ~(BIT0);
case PWM_0:
PWM1TCR &= ~(BIT0);
break;
#endif
}
} }
void pwm_poweron(pwm_t dev) void pwm_poweron(pwm_t dev)
{ {
switch (dev) { assert(dev == PWM_DEV(0));
#if PWM_0_EN PCONP |= PCPWM1;
case PWM_0:
PCONP |= PCPWM1;
break;
#endif
}
} }
void pwm_poweroff(pwm_t dev) void pwm_poweroff(pwm_t dev)
{ {
switch (dev) { assert(dev == PWM_DEV(0));
#if PWM_0_EN PCONP &= ~(PCPWM1);
case PWM_0:
PCONP &= ~(PCPWM1);
break;
#endif
}
} }
#endif /* (PWM_0_EN || PWM_1_EN) */ #endif /* PWM_NUMOF */