*
* Copyright 2005 Develer S.r.l. (http://www.develer.com/)
* -->
+ * \defgroup pwm_driver PWM driver
+ * \ingroup drivers
+ * \{
+ * \brief Pulse Width Modulation (PWM) driver.
*
- * \version $Id$
- *
- * \brief PWM driver (interface)
- *
- * \version $Id$
* \author Francesco Sacchi <batt@develer.com>
* \author Daniele Basile <asterix@develer.com>
*
- * $WIZARD_MODULE = {
- * "name" : "pwm",
- * "depends" : [],
- * "configuration" : "bertos/cfg/cfg_pwm.h"
- * }
+ * $WIZ$ module_name = "pwm"
+ * $WIZ$ module_configuration = "bertos/cfg/cfg_pwm.h"
+ * $WIZ$ module_hw = "bertos/hw/pwm_map.h"
+ * $WIZ$ module_supports = "not avr and not cm3"
*/
#ifndef DRV_PWM_H
#define DRV_PWM_H
-#include "hw/pwm_map.h"
-
#include <cpu/attr.h>
-#include CPU_HEADER(pwm)
-
#include <cfg/compiler.h>
+#include "cfg/cfg_pwm.h"
+/**
+ * Maximum PWM duty cycle value (100%)
+ */
#define PWM_MAX_DUTY ((pwm_duty_t)0xFFFF)
#define PWM_MAX_PERIOD 0xFFFF
#define PWM_MAX_PERIOD_LOG2 16
/**
- * PWM type define.
+ * Type for PWM duty cycle.
+ * The value is represented as a 16bit unsigned integer, so it ranges from 0 (0%)
+ * to PWM_MAX_DUTY (0xFFFF = 100%).
*/
typedef uint16_t pwm_duty_t;
+
+/**
+ * Type for PWM frequency.
+ * Unit of measure is Hz.
+ */
typedef uint32_t pwm_freq_t;
+#if !CFG_PWM_ENABLE_OLD_API || defined(__doxygen__)
+ /**
+ * \defgroup pwm_api PWM API
+ * With this driver you can control a device with multiple PWM channels.
+ * You can enable/disable each channel indipendently and also set frequency
+ * and duty cycle.
+ *
+ * API usage example:
+ * \code
+ * Pwm pwm; // declare a context structure
+ * pwm_init(&pwm, 0); // init pwm channel 0
+ * pwm_setFrequency(&pwm, 1000); // Set frequency of channel 0 to 1000Hz
+ * pwm_setDuty(&pwm, 0x7FFF); // Set duty to 50% (0xFFFF/2)
+ * pwm_enable(&pwm, true); // Activate the output
+ * \endcode
+ * \{
+ */
+ /**
+ * Enum describing PWM polarities.
+ */
+ typedef enum PwmPolarity
+ {
+ /** High pulse: increasing duty increases the part of the signal at high level. */
+ PWM_POL_HIGH_PULSE,
+ /** Positive pulse: same as High pulse. */
+ PWM_POL_POSITIVE = PWM_POL_HIGH_PULSE,
+ /** Low pulse: increasing duty increases the part of the signal at low level. */
+ PWM_POL_LOW_PULSE,
+ /** Negative pulse: same as Low pulse. */
+ PWM_POL_NEGATIVE = PWM_POL_LOW_PULSE,
+ } PwmPolarity;
-/**
- * Set PWM polarity of pwm \p dev.
- */
-INLINE void pwm_setPolarity(PwmDev dev, bool pol)
-{
- pwm_hw_setPolarity(dev, pol);
-}
+ struct PwmHardware; //Fwd declaration
-void pwm_setDuty(PwmDev dev, pwm_duty_t duty);
-void pwm_setFrequency(PwmDev dev, pwm_freq_t freq);
-void pwm_enable(PwmDev dev, bool state);
-void pwm_init(void);
+ /**
+ * PWM context structure.
+ */
+ typedef struct Pwm
+ {
+ unsigned ch;
+ pwm_duty_t duty;
+ PwmPolarity pol;
+ bool enabled;
+ struct PwmHardware *hw;
+ } Pwm;
-/**
+ void pwm_setDuty(Pwm *ctx, pwm_duty_t duty);
+ void pwm_setFrequency(Pwm *ctx, pwm_freq_t freq);
+ void pwm_setPolarity(Pwm *ctx, PwmPolarity pol);
+ void pwm_enable(Pwm *ctx, bool state);
+ void pwm_init(Pwm *ctx, unsigned channel);
+ /** \} */ //defgroup pwm_api
+#endif
+
+
+#if CFG_PWM_ENABLE_OLD_API
+ /**
+ * \defgroup pwm_old_api Old PWM API
+ * This API has strong limititations, so it has been deprecated.
+ * It is active by default for backward compatibility reasons, but
+ * for new projects please use the new PWM API.
+ * In order to disable this API, check CFG_PWM_ENABLE_OLD_API.
+ * \see pwm_api
+ * \see CFG_PWM_ENABLE_OLD_API
+ * \{
+ */
+
+ #include CPU_HEADER(pwm)
+ #include "hw/pwm_map.h"
+
+ /**
+ * Set PWM polarity of pwm \p dev.
+ * \param dev PWM channel.
+ * \param pol if false positive polarity pulses are generated,
+ * if true negative polarity pulses are generated.
+ * \warning This function has to be called with PWM disabled, otherwise
+ * the output value will be undefined.
+ */
+ INLINE void pwm_setPolarity(PwmDev dev, bool pol)
+ {
+ pwm_hw_setPolarity(dev, pol);
+ }
+
+ void pwm_setDuty(PwmDev dev, pwm_duty_t duty);
+ void pwm_setFrequency(PwmDev dev, pwm_freq_t freq);
+ void pwm_enable(PwmDev dev, bool state);
+ void pwm_init(void);
+ /** \} */ //defgroup pwm_old_api
+#endif
+
+/*
* Test function prototypes.
*
* See pwm_test.c for implemntation of these functions.
*/
-int pwm_testRun(void);
-int pwm_testSetUp(void);
+void pwm_testRun(void);
+int pwm_testSetup(void);
+/* For backward compatibility */
+#define pwm_testSetUp() pwm_testSetup()
int pwm_testTearDown(void);
+
+/** \} */ //defgroup pwm_driver
+
#endif /* DRV_PWM_H */
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