+++ /dev/null
-
-/**
- * \file
- * <!--
- * Copyright 2004, 2008 Develer S.r.l. (http://www.develer.com/)
- * All Rights Reserved.
- * -->
- *
- * \brief Compute, save and load ramps for stepper motors (interace)
- *
- * \version $Id$
- *
- * \author Simone Zinanni <s.zinanni@develer.com>
- * \author Giovanni Bajo <rasky@develer.com>
- * \author Daniele Basile <asterix@develer.com>
- *
- * The acceleration ramp is used to properly accelerate a stepper motor. The main
- * entry point is the function ramp_evaluate(), which must be called at every step
- * of the motor: it gets as input the time elapsed since the stepper started
- * accelerating, and returns the time to wait before sending the next step. A pseudo
- * usage pattern is as follows:
- *
- * <pre>
- * float time = 0;
- * while (1)
- * {
- * float delta = ramp_evaluate(&my_ramp, time);
- * sleep(delta);
- * do_motor_step();
- * time += delta;
- * }
- * </pre>
- *
- * A similar pattern can be used to decelerate (it is sufficient to move the total
- * time backward, such as "time -= delta").
- *
- * The ramp can be configured with ramp_setup(), providing it with the minimum and
- * maximum operating frequency of the motor, and the total acceleration time in
- * milliseconds (that is, the time that will be needed to accelerate from the
- * minimum frequency to the maximum frequency).
- *
- * Both a very precise floating point and a very fast fixed point implementation
- * of the ramp evaluation are provided. The fixed point is hand-optimized assembly
- * for DSP56000 (but a portable C version of it can be easily written, see the
- * comments in the code).
- *
- */
-
-#ifndef ALGO_RAMP_H
-#define ALGO_RAMP_H
-
-#include <cfg/compiler.h>
-#include "hw_stepper.h"
-
-/**
- * Define whether the ramp will use floating point calculation within ramp_evaluate().
- * Otherwise, a less precise fixed point version will be used, which is faster on
- * platforms which do no support floating point operations.
- *
- * \note Floating point operations will be always done within ramp_compute() to
- * precalculate values, so there has to be at least a floating point emulation support.
- */
-#define RAMP_USE_FLOATING_POINT 0
-
-
-#if !RAMP_USE_FLOATING_POINT
-
- /**
- * Number of least-significant bits which are stripped away during ramp evaluation.
- * This setting allows to specify larger ramps at the price of less precision.
- *
- * The maximum ramp size allowed is 2^(24 + RAMP_CLOCK_SHIFT_PRECISION), in clocks.
- * For instance, using RAMP_CLOCK_SHIFT_PRECISION 1, and a 8x prescaler, the maximum
- * length of a ramp is about 6.7 secs. Raising RAMP_CLOCK_SHIFT_PRECISION to 2
- * brings the maximum length to 13.4 secs, at the price of less precision.
- *
- * ramp_compute() will check that the length is below the maximum allowed through
- * a runtime assertion.
- *
- * \note This macro is used only for the fixed-point version of the ramp.
- */
- #define RAMP_CLOCK_SHIFT_PRECISION 2
-#endif
-
-
-///< Negative pulse width for ramp
-#define RAMP_PULSE_WIDTH 50
-
-///< Default ramp
-#define RAMP_DEF_TIME 6000000 ///< microsecs
-#define RAMP_DEF_MAXFREQ 5000 ///< Hz
-#define RAMP_DEF_MINFREQ 200 ///< Hz
-#define RAMP_DEF_POWERRUN 10 ///< 10 deciampere (1 ampere)
-#define RAMP_DEF_POWERIDLE 1 ///< 1 deciampere
-
-
-/**
- * Convert microseconds to timer clock ticks
- */
-#define TIME2CLOCKS(micros) ((uint32_t)(micros) * (STEPPER_CLOCK / 1000000))
-
-/**
- * Convert timer clock ticks back to microseconds
- */
-#define CLOCKS2TIME(clocks) ((uint32_t)(clocks) / (STEPPER_CLOCK / 1000000))
-
-/**
- * Convert microseconds to Hz
- */
-#define MICROS2FREQ(micros) (1000000UL / ((uint32_t)(micros)))
-
-/**
- * Convert frequency (in Hz) to time (in microseconds)
- */
-#define FREQ2MICROS(hz) (1000000UL / ((uint32_t)(hz)))
-
-
-
-/**
- * Structure holding pre-calculated data for speeding up real-time evaluation
- * of the ramp. This structure is totally different between the fixed and the
- * floating point version of the code.
- *
- * Consult the file-level documentation of ramp.c for more information about
- * the values of this structure.
- */
-struct RampPrecalc
-{
-#if RAMP_USE_FLOATING_POINT
- float beta;
- float alpha;
- float gamma;
-#else
- uint16_t max_div_min;
- uint32_t inv_total_time;
-#endif
-};
-
-
-/**
- * Ramp structure
- */
-struct Ramp
-{
- uint32_t clocksRamp;
- uint16_t clocksMinWL;
- uint16_t clocksMaxWL;
-
- struct RampPrecalc precalc; ///< pre-calculated values for speed
-};
-
-
-/*
- * Function prototypes
- */
-void ramp_compute(
- struct Ramp * ramp,
- uint32_t clocksInRamp,
- uint16_t clocksInMinWavelength,
- uint16_t clocksInMaxWavelength);
-
-
-/** Setup an acceleration ramp for a stepper motor
- *
- * \param ramp Ramp to fill
- * \param length Length of the ramp (milliseconds)
- * \param minFreq Minimum operating frequency of the motor (hertz)
- * \param maxFreq Maximum operating frequency of the motor (hertz)
- *
- */
-void ramp_setup(struct Ramp* ramp, uint32_t length, uint32_t minFreq, uint32_t maxFreq);
-
-
-/**
- * Initialize a new ramp with default values
- */
-void ramp_default(struct Ramp *ramp);
-
-
-/**
- * Evaluate the ramp at the given point. Given a \a ramp, and the current \a clock since
- * the start of the acceleration, compute the next step, that is the interval at which
- * send the signal to the motor.
- *
- * \note The fixed point version does not work when curClock is zero. Anyway,
- * the first step is always clocksMaxWL, as stored within the ramp structure.
- */
-#if RAMP_USE_FLOATING_POINT
- float ramp_evaluate(const struct Ramp* ramp, float curClock);
-#else
- uint16_t ramp_evaluate(const struct Ramp* ramp, uint32_t curClock);
-#endif
-
-
-/** Self test */
-void ramp_test(void);
-
-#endif /* ALGO_RAMP_H */
-
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