adjust root folder
This commit is contained in:
Steve Karg
@@ -0,0 +1,244 @@
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/**
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* \file
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*
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* \brief PWM service for XMEGA.
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*
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* Copyright (c) 2012 Atmel Corporation. All rights reserved.
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*
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* \asf_license_start
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||||
*
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||||
* \page License
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||||
*
|
||||
* Redistribution and use in source and binary forms, with or without
|
||||
* modification, are permitted provided that the following conditions are met:
|
||||
*
|
||||
* 1. Redistributions of source code must retain the above copyright notice,
|
||||
* this list of conditions and the following disclaimer.
|
||||
*
|
||||
* 2. Redistributions in binary form must reproduce the above copyright notice,
|
||||
* this list of conditions and the following disclaimer in the documentation
|
||||
* and/or other materials provided with the distribution.
|
||||
*
|
||||
* 3. The name of Atmel may not be used to endorse or promote products derived
|
||||
* from this software without specific prior written permission.
|
||||
*
|
||||
* 4. This software may only be redistributed and used in connection with an
|
||||
* Atmel microcontroller product.
|
||||
*
|
||||
* THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED
|
||||
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
|
||||
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
|
||||
* EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR
|
||||
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
||||
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
||||
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
||||
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
|
||||
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
|
||||
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
||||
* POSSIBILITY OF SUCH DAMAGE.
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||||
*
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||||
* \asf_license_stop
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||||
*
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*/
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#include <asf.h>
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/**
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* \brief Calculate TC settings from PWM frequency
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*
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* This function will find the correct TC settings (clock prescaler and
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* period) which will give the wanted PWM frequency.
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*
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* \note Since we want to be able to run the PWM at all duty-cycles ranging
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* from 0-100%, we require a period of at least 100 to achieve this. Thus, the
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* highest possible PWM frequency is CPU frequency / 100.
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*
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* \param config Pointer to PWM configuration.
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* \param freq_hz Wanted PWM frequency in Hz.
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*/
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void pwm_set_frequency(struct pwm_config *config, uint16_t freq_hz)
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{
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uint32_t cpu_hz = sysclk_get_cpu_hz();
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uint16_t smallest_div;
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uint16_t dividor;
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/* Avoid division by zero. */
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Assert(freq_hz != 0);
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/* Calculate the smallest divider for the requested frequency
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related to the CPU frequency */
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smallest_div = cpu_hz / freq_hz / 0xFFFF;
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if (smallest_div < 1) {
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dividor = 1;
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config->clk_sel = PWM_CLK_DIV1;
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} else if (smallest_div < 2) {
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dividor = 2;
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config->clk_sel = PWM_CLK_DIV2;
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} else if (smallest_div < 4) {
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dividor = 4;
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config->clk_sel = PWM_CLK_DIV4;
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} else if (smallest_div < 8) {
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dividor = 8;
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config->clk_sel = PWM_CLK_DIV8;
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} else if (smallest_div < 64) {
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dividor = 64;
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config->clk_sel = PWM_CLK_DIV64;
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} else if (smallest_div < 256) {
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dividor = 256;
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config->clk_sel = PWM_CLK_DIV256;
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} else {
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dividor = 1024;
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config->clk_sel = PWM_CLK_DIV1024;
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}
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/* Calculate the period from the just found divider */
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config->period = cpu_hz / dividor / freq_hz;
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/* Make sure our period is at least 100 ticks so we are able to provide
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a full range (0-100% duty cycle */
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if (config->period < 100) {
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/* The period is too short. */
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config->clk_sel = PWM_CLK_OFF;
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config->period = 0;
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Assert(false);
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}
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}
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/**
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* \brief Initialize PWM configuration struct and set correct I/O pin to output
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*
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* \param config Pointer to PWM configuration struct.
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* \param tc \ref pwm_tc_t "TC" to use for this PWM.
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* \param channel \ref pwm_channel_t "CC channel" to use for this PWM.
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* \param freq_hz Frequency to use for this PWM.
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*/
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void pwm_init(struct pwm_config *config, enum pwm_tc_t tc,
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enum pwm_channel_t channel, uint16_t freq_hz)
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{
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/* Number of channels for this TC */
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uint8_t num_chan = 0;
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UNUSED(num_chan);
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/* Set TC and correct I/O pin to output */
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switch (tc) {
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#if defined(TCC0)
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case PWM_TCC0:
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config->tc = &TCC0;
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PORTC.DIR |= (1 << (channel-1));
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num_chan = 4;
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break;
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#endif
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#if defined(TCC1)
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case PWM_TCC1:
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config->tc = &TCC1;
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PORTC.DIR |= (1 << (channel+3));
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num_chan = 2;
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break;
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#endif
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#if defined(TCD0)
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case PWM_TCD0:
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config->tc = &TCD0;
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PORTD.DIR |= (1 << (channel-1));
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num_chan = 4;
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break;
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#endif
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#if defined(TCD1)
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case PWM_TCD1:
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config->tc = &TCD1;
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PORTD.DIR |= (1 << (channel+3));
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num_chan = 2;
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break;
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#endif
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#if defined(TCE0)
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case PWM_TCE0:
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config->tc = &TCE0;
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PORTE.DIR |= (1 << (channel-1));
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num_chan = 4;
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break;
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#endif
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#if defined(TCE1)
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case PWM_TCE1:
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config->tc = &TCE1;
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PORTE.DIR |= (1 << (channel+3));
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num_chan = 2;
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break;
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#endif
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#if defined(TCF0)
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case PWM_TCF0:
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config->tc = &TCF0;
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PORTF.DIR |= (1 << (channel-1));
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num_chan = 4;
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break;
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#endif
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#if defined(TCF1)
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case PWM_TCF1:
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config->tc = &TCF1;
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PORTF.DIR |= (1 << (channel+3));
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num_chan = 2;
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break;
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#endif
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default:
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Assert(false);
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break;
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}
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/* Make sure we are not given a channel number larger
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than this TC can handle */
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Assert(channel <= num_chan);
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config->channel = channel;
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/* Set the correct cc_mask */
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switch (channel) {
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case PWM_CH_A:
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config->cc_mask = TC_CCAEN;
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break;
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case PWM_CH_B:
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config->cc_mask = TC_CCBEN;
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break;
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case PWM_CH_C:
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config->cc_mask = TC_CCCEN;
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break;
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case PWM_CH_D:
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config->cc_mask = TC_CCDEN;
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break;
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default:
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Assert(false);
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break;
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}
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/* Enable peripheral clock for this TC */
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tc_enable(config->tc);
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/* Set this TC's waveform generator in single slope mode */
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tc_set_wgm(config->tc, TC_WG_SS);
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/* Default values (disable TC and set minimum period)*/
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config->period = 0;
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config->clk_sel = PWM_CLK_OFF;
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tc_write_clock_source(config->tc, PWM_CLK_OFF);
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/* Set the PWM frequency */
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pwm_set_frequency(config, freq_hz);
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}
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/**
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* \brief Start a PWM channel
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*
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* This function enables a channel with a given duty cycle.
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*
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* \param *config Pointer to the PWM configuration struct
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* \param duty_cycle_scale Duty cycle as a value between 0 and 100.
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*/
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void pwm_start(struct pwm_config *config, uint8_t duty_cycle_scale)
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{
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/* Set given duty cycle */
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pwm_set_duty_cycle_percent(config, duty_cycle_scale);
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/* Set correct TC period */
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tc_write_period(config->tc, config->period);
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/* Enable CC channel for this TC */
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tc_enable_cc_channels(config->tc, config->cc_mask);
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/* Enable TC by setting correct clock prescaler */
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tc_write_clock_source(config->tc, config->clk_sel);
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}
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@@ -0,0 +1,352 @@
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/**
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* \file
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*
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* \brief PWM service for XMEGA.
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*
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* Copyright (c) 2012 Atmel Corporation. All rights reserved.
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*
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||||
* \asf_license_start
|
||||
*
|
||||
* \page License
|
||||
*
|
||||
* Redistribution and use in source and binary forms, with or without
|
||||
* modification, are permitted provided that the following conditions are met:
|
||||
*
|
||||
* 1. Redistributions of source code must retain the above copyright notice,
|
||||
* this list of conditions and the following disclaimer.
|
||||
*
|
||||
* 2. Redistributions in binary form must reproduce the above copyright notice,
|
||||
* this list of conditions and the following disclaimer in the documentation
|
||||
* and/or other materials provided with the distribution.
|
||||
*
|
||||
* 3. The name of Atmel may not be used to endorse or promote products derived
|
||||
* from this software without specific prior written permission.
|
||||
*
|
||||
* 4. This software may only be redistributed and used in connection with an
|
||||
* Atmel microcontroller product.
|
||||
*
|
||||
* THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED
|
||||
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
|
||||
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
|
||||
* EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR
|
||||
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
||||
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
||||
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
||||
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
|
||||
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
|
||||
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
||||
* POSSIBILITY OF SUCH DAMAGE.
|
||||
*
|
||||
* \asf_license_stop
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||||
*
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||||
*/
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#ifndef PWM_H
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#define PWM_H
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#include "tc.h"
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#ifdef __cplusplus
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extern "C" {
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#endif
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/**
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* \defgroup pwm_group XMEGA Pulse Width Modulation (PWM) service
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*
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* See \ref pwm_quickstart.
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*
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* This is a service for single slope wave form generation on the XMEGA.
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* It provides functions for enabling, disabling and configuring the TC modules
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* in single slope PWM mode.
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*
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* The API uses a \ref pwm_config "structure" which contain the configuration.
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* This structure must be set up before the PWM can be started.
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*
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* \section dependencies Dependencies
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* This driver depends on the following modules:
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* - \ref tc_group to set up TC in PWM mode.
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* @{
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*/
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/**
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* \brief PWM compare channel index
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*/
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enum pwm_channel_t {
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/** Channel A. PWM output on pin 0 */
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PWM_CH_A = 1,
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/** Channel B. PWM output on pin 1 */
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PWM_CH_B = 2,
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/** Channel C. PWM output on pin 2 */
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PWM_CH_C = 3,
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/** Channel D. PWM output on pin 3 */
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PWM_CH_D = 4,
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};
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|
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/**
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* \brief Valid timer/counters to use
|
||||
* \note Not all timer/counters are available on all devices.
|
||||
* Please refer to the datasheet for more information on what
|
||||
* timer/counters are available for the device you are using.
|
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*/
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enum pwm_tc_t {
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/** PWM on port C, pin 0, 1, 2 or 3 (depending on
|
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\ref pwm_channel_t "channel") */
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PWM_TCC0,
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/** PWM on port C, pin 4 or 5 (depending on
|
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\ref pwm_channel_t "channel") */
|
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PWM_TCC1,
|
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/** PWM on port D, pin 0, 1, 2 or 3 (depending on
|
||||
\ref pwm_channel_t "channel") */
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PWM_TCD0,
|
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/** PWM on port D, pin 4 or 5 (depending on
|
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\ref pwm_channel_t "channel") */
|
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PWM_TCD1,
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/** PWM on port E, pin 0, 1, 2 or 3 (depending on
|
||||
\ref pwm_channel_t "channel") */
|
||||
PWM_TCE0,
|
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/** PWM on port E, pin 4 or 5 (depending on
|
||||
\ref pwm_channel_t "channel") */
|
||||
PWM_TCE1,
|
||||
/** PWM on port F, pin 0, 1, 2 or 3 (depending on
|
||||
\ref pwm_channel_t "channel") */
|
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PWM_TCF0,
|
||||
/** PWM on port F, pin 4 or 5 (depending on
|
||||
\ref pwm_channel_t "channel") */
|
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PWM_TCF1,
|
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};
|
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|
||||
/**
|
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* \brief Valid clock source indexes
|
||||
*/
|
||||
enum pwm_clk_sel {
|
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PWM_CLK_OFF = TC_CLKSEL_OFF_gc,
|
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PWM_CLK_DIV1 = TC_CLKSEL_DIV1_gc,
|
||||
PWM_CLK_DIV2 = TC_CLKSEL_DIV2_gc,
|
||||
PWM_CLK_DIV4 = TC_CLKSEL_DIV4_gc,
|
||||
PWM_CLK_DIV8 = TC_CLKSEL_DIV8_gc,
|
||||
PWM_CLK_DIV64 = TC_CLKSEL_DIV64_gc,
|
||||
PWM_CLK_DIV256 = TC_CLKSEL_DIV256_gc,
|
||||
PWM_CLK_DIV1024 = TC_CLKSEL_DIV1024_gc,
|
||||
};
|
||||
|
||||
/**
|
||||
* \brief PWM configuration
|
||||
*/
|
||||
struct pwm_config {
|
||||
void *tc;
|
||||
enum pwm_channel_t channel;
|
||||
enum tc_cc_channel_mask_enable_t cc_mask;
|
||||
enum pwm_clk_sel clk_sel;
|
||||
uint16_t period;
|
||||
};
|
||||
|
||||
/** \brief Interrupt callback type */
|
||||
typedef void (*pwm_callback_t) (void);
|
||||
|
||||
void pwm_init(struct pwm_config *config, enum pwm_tc_t tc,
|
||||
enum pwm_channel_t channel, uint16_t freq_hz);
|
||||
void pwm_set_frequency(struct pwm_config *config, uint16_t freq_hz);
|
||||
void pwm_start(struct pwm_config *config, uint8_t duty_cycle_scale);
|
||||
|
||||
/**
|
||||
* \brief Function to set PWM duty cycle
|
||||
*
|
||||
* The duty cycle can be set on a scale between 0-100%. This value
|
||||
* will be used to update the CCx register for the selected PWM channel.
|
||||
*
|
||||
* \param *config Pointer to the PWM configuration struct
|
||||
* \param duty_cycle_scale Duty cycle as a value between 0 and 100.
|
||||
*/
|
||||
static inline void pwm_set_duty_cycle_percent(struct pwm_config *config,
|
||||
uint8_t duty_cycle_scale)
|
||||
{
|
||||
Assert( duty_cycle_scale <= 100 );
|
||||
tc_write_cc_buffer(config->tc, config->channel,
|
||||
(uint16_t)(((uint32_t)config->period *
|
||||
(uint32_t)duty_cycle_scale) / 100));
|
||||
}
|
||||
|
||||
/**
|
||||
* \brief Function that stops the PWM timer
|
||||
*
|
||||
* The PWM timer is stopped by writing the prescaler register to "clock off"
|
||||
*
|
||||
* \param *config Pointer to the PWM configuration struct
|
||||
*/
|
||||
static inline void pwm_stop(struct pwm_config *config)
|
||||
{
|
||||
tc_write_clock_source(config->tc, TC_CLKSEL_OFF_gc);
|
||||
}
|
||||
|
||||
/**
|
||||
* \brief Disable the PWM timer
|
||||
*
|
||||
* This function disables the peripheral clock for the timer and shut down
|
||||
* module when unused in order to save power.
|
||||
*
|
||||
* \param *config Pointer to the PWM configuration struct
|
||||
*/
|
||||
static inline void pwm_disable(struct pwm_config *config)
|
||||
{
|
||||
pwm_stop(config);
|
||||
tc_disable(config->tc);
|
||||
}
|
||||
|
||||
/**
|
||||
* \brief Function that resets the PWM timer
|
||||
*
|
||||
* This function reset the CNT register for the selected timer used for PWM
|
||||
*
|
||||
* \param *config Pointer to the PWM configuration struct
|
||||
*/
|
||||
static inline void pwm_timer_reset(struct pwm_config *config)
|
||||
{
|
||||
tc_write_count(config->tc, 0);
|
||||
}
|
||||
|
||||
/**
|
||||
* \brief Callback function for timer overflow interrupts
|
||||
*
|
||||
* This function enables T/C overflow interrupts (low level interrupts)
|
||||
* and defines the callback function for the overflow ISR interrupt routine.
|
||||
*
|
||||
* \param *config Pointer to the PWM configuration struct
|
||||
* \param callback Callback function
|
||||
*/
|
||||
static inline void pwm_overflow_int_callback(struct pwm_config *config,
|
||||
pwm_callback_t callback)
|
||||
{
|
||||
tc_set_overflow_interrupt_level(config->tc, TC_INT_LVL_LO);
|
||||
tc_set_overflow_interrupt_callback(config->tc, callback);
|
||||
}
|
||||
|
||||
/** @} */
|
||||
|
||||
#ifdef __cplusplus
|
||||
}
|
||||
#endif
|
||||
|
||||
/**
|
||||
* \page pwm_quickstart Quickstart guide for AVR XMEGA PWM service
|
||||
*
|
||||
* This is the quickstart guide for the \ref pwm_group,
|
||||
* with step-by-step instructions on how to configure and use the service in a
|
||||
* selection of use cases.
|
||||
*
|
||||
* The use cases contain several code fragments. The code fragments in the
|
||||
* steps for setup can be copied into a custom initialization function, while
|
||||
* the steps for usage can be copied into, e.g., the main application function.
|
||||
*
|
||||
* \section basic_use_case Basic use case
|
||||
* In the most basic use case, we configure one PWM channel in non-interrupt
|
||||
* mode.
|
||||
*
|
||||
* \section pwm_basic_use_case_setup Setup steps
|
||||
* \subsection pwm_basic_use_case_setup_code Example code
|
||||
* Add to application C-file:
|
||||
* \code
|
||||
* struct pwm_config pwm_cfg;
|
||||
*
|
||||
* sysclk_init();
|
||||
* pwm_init(&pwm_cfg, PWM_TCE0, PWM_CH_A, 500);
|
||||
* \endcode
|
||||
*
|
||||
* \subsection pwm_basic_use_case_setup_flow Workflow
|
||||
* -# Ensure that \ref conf_clock.h is present for the driver.
|
||||
* \note This file is only for the driver and should not be included by the
|
||||
* user.
|
||||
* -# Define config struct for PWM module:
|
||||
* \code struct pwm_config pwm_cfg; \endcode
|
||||
* -# Initialize sysclock module:
|
||||
* \code sysclk_init();\endcode
|
||||
* -# Initialize config struct and set up PWM with frequency of 500 Hz.\n
|
||||
* \code pwm_init(&pwm_cfg, PWM_TCE0, PWM_CH_A, 500); \endcode
|
||||
* \note Since the timer/counter \ref PWM_TCE0 and channel \ref PWM_CH_A
|
||||
* is used, the PWM will be output on port E, pin 0.
|
||||
* See \ref pwm_tc_t and \ref pwm_channel_t for more information
|
||||
* on what port/pin is used for different timer/counters.
|
||||
|
||||
* \attention This step must not be skipped or the initial content of the
|
||||
* structs will be unpredictable, possibly causing misconfiguration.
|
||||
*
|
||||
* \section pwm_basic_use_case_usage Usage steps
|
||||
* \subsection pwm_basic_use_case_usage_code Example code
|
||||
* Add to, e.g., main loop in application C-file:
|
||||
* \code pwm_start(&pwm_config, 50); \endcode
|
||||
*
|
||||
* \subsection pwm_basic_use_case_usage_flow Workflow
|
||||
* -# Start PWM with 50% duty cycle:
|
||||
* \code pwm_start(&pwm_config, 50); \endcode
|
||||
*
|
||||
* \section pwm_use_cases Advanced use cases
|
||||
* For more advanced use of the PWM service, see the following use cases:
|
||||
* - \subpage pwm_use_case_1 : PWM with interrupt
|
||||
*/
|
||||
/**
|
||||
* \page pwm_use_case_1 Use case #1
|
||||
* In this use case the PWM module is configured with overflow interrupt.
|
||||
*
|
||||
* \section pwm_use_case_1_setup Setup steps
|
||||
* \subsection pwm_use_case_1_setup_code Example code
|
||||
*
|
||||
* Add to application C-file:
|
||||
* \code
|
||||
* struct pwm_config pwm_cfg;
|
||||
*
|
||||
* void my_callback(void)
|
||||
* {
|
||||
* do_something();
|
||||
* }
|
||||
|
||||
* void pwm_init(void)
|
||||
* {
|
||||
* pmic_init();
|
||||
* sysclk_init();
|
||||
*
|
||||
* cpu_irq_enable();
|
||||
*
|
||||
* pwm_init(&pwm_cfg, PWM_TCE0, PWM_CH_A, 75);
|
||||
* pwm_overflow_int_callback(&pwm_cfg, my_callback);
|
||||
* }
|
||||
* \endcode
|
||||
*
|
||||
* \subsection pwm_use_case_1_setup_flow Workflow
|
||||
* -# Define config struct for PWM module:
|
||||
* \code struct pwm_config pwm_cfg; \endcode
|
||||
* -# Define a callback function in the application which does whatever task
|
||||
* you want it to do:
|
||||
* \code
|
||||
* void my_callback(void)
|
||||
* {
|
||||
* do_something();
|
||||
* }
|
||||
* \endcode
|
||||
* -# Initialize interrupt controller module:
|
||||
* \code pmic_init();\endcode
|
||||
* -# Initialize sysclock module:
|
||||
* \code sysclk_init();\endcode
|
||||
* -# Enable global interrupts:
|
||||
* \code cpu_irq_enable();\endcode
|
||||
* -# Initialize config struct and set up PWM with frequency of 75 Hz:
|
||||
* \code pwm_init(&pwm_cfg, PWM_TCE0, PWM_CH_A, 75); \endcode
|
||||
* \note Since the timer/counter \ref PWM_TCE0 and channel \ref PWM_CH_A
|
||||
* is used, the PWM will be output on port E, pin 0.
|
||||
* See \ref pwm_tc_t and \ref pwm_channel_t for more information
|
||||
* on what port/pin is used for different timer/counters.
|
||||
* \attention This step must not be skipped or the initial content of the
|
||||
* structs will be unpredictable, possibly causing misconfiguration.
|
||||
* -# Set callback function on PWM TC channel overflow:
|
||||
* \code pwm_overflow_int_callback(&pwm_cfg, my_callback); \endcode
|
||||
*
|
||||
* \section pwm_use_case_1_usage Usage steps
|
||||
* \subsection pwm_use_case_1_usage_code Example code
|
||||
* Add to, e.g., main loop in application C-file:
|
||||
* \code pwm_start(&pwm_cfg, 50); \endcode
|
||||
*
|
||||
* \subsection pwm_basic_use_case_usage_flow Workflow
|
||||
* -# Start PWM with 50% duty cycle:
|
||||
* \code pwm_start(&pwm_cfg, 50); \endcode
|
||||
*
|
||||
*/
|
||||
|
||||
#endif /* PWM_H */
|
||||
Reference in New Issue
Block a user