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-rw-r--r--libraries/Servo/Servo.cpp150
-rw-r--r--libraries/Servo/Servo.h196
-rw-r--r--libraries/Servo/rules.mk29
3 files changed, 375 insertions, 0 deletions
diff --git a/libraries/Servo/Servo.cpp b/libraries/Servo/Servo.cpp
new file mode 100644
index 0000000..ecb85e6
--- /dev/null
+++ b/libraries/Servo/Servo.cpp
@@ -0,0 +1,150 @@
+/******************************************************************************
+ * The MIT License
+ *
+ * Copyright (c) 2010, LeafLabs, LLC.
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy,
+ * modify, merge, publish, distribute, sublicense, and/or sell copies
+ * of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *****************************************************************************/
+
+#include "Servo.h"
+
+#include <wirish/boards.h>
+#include <wirish/io.h>
+#include <wirish/pwm.h>
+#include <wirish/wirish_math.h>
+
+// 20 millisecond period config. For a 1-based prescaler,
+//
+// (prescaler * overflow / CYC_MSEC) msec = 1 timer cycle = 20 msec
+// => prescaler * overflow = 20 * CYC_MSEC
+//
+// This picks the smallest prescaler that allows an overflow < 2^16.
+#define MAX_OVERFLOW ((1 << 16) - 1)
+#define CYC_MSEC (1000 * CYCLES_PER_MICROSECOND)
+#define TAU_MSEC 20
+#define TAU_USEC (TAU_MSEC * 1000)
+#define TAU_CYC (TAU_MSEC * CYC_MSEC)
+#define SERVO_PRESCALER (TAU_CYC / MAX_OVERFLOW + 1)
+#define SERVO_OVERFLOW ((uint16)round((double)TAU_CYC / SERVO_PRESCALER))
+
+// Unit conversions
+#define US_TO_COMPARE(us) ((uint16)map((us), 0, TAU_USEC, 0, SERVO_OVERFLOW))
+#define COMPARE_TO_US(c) ((uint32)map((c), 0, SERVO_OVERFLOW, 0, TAU_USEC))
+#define ANGLE_TO_US(a) ((uint16)(map((a), this->minAngle, this->maxAngle, \
+ this->minPW, this->maxPW)))
+#define US_TO_ANGLE(us) ((int16)(map((us), this->minPW, this->maxPW, \
+ this->minAngle, this->maxAngle)))
+
+Servo::Servo() {
+ this->resetFields();
+}
+
+bool Servo::attach(uint8 pin,
+ uint16 minPW,
+ uint16 maxPW,
+ int16 minAngle,
+ int16 maxAngle) {
+ timer_dev *tdev = PIN_MAP[pin].timer_device;
+
+ if (tdev == NULL) {
+ // don't reset any fields or ASSERT(0), to keep driving any
+ // previously attach()ed servo.
+ return false;
+ }
+
+ if (this->attached()) {
+ this->detach();
+ }
+
+ this->pin = pin;
+ this->minPW = minPW;
+ this->maxPW = maxPW;
+ this->minAngle = minAngle;
+ this->maxAngle = maxAngle;
+
+ pinMode(pin, PWM);
+
+ timer_pause(tdev);
+ timer_set_prescaler(tdev, SERVO_PRESCALER - 1); // prescaler is 1-based
+ timer_set_reload(tdev, SERVO_OVERFLOW);
+ timer_generate_update(tdev);
+ timer_resume(tdev);
+
+ return true;
+}
+
+bool Servo::detach() {
+ if (!this->attached()) {
+ return false;
+ }
+
+ timer_dev *tdev = PIN_MAP[this->pin].timer_device;
+ uint8 tchan = PIN_MAP[this->pin].timer_channel;
+ timer_set_mode(tdev, tchan, TIMER_DISABLED);
+
+ this->resetFields();
+
+ return true;
+}
+
+void Servo::write(int degrees) {
+ degrees = constrain(degrees, this->minAngle, this->maxAngle);
+ this->writeMicroseconds(ANGLE_TO_US(degrees));
+}
+
+int Servo::read() const {
+ int a = US_TO_ANGLE(this->readMicroseconds());
+ // map() round-trips in a weird way we mostly correct for here;
+ // the round-trip is still sometimes off-by-one for write(1) and
+ // write(179).
+ return a == this->minAngle || a == this->maxAngle ? a : a + 1;
+}
+
+void Servo::writeMicroseconds(uint16 pulseWidth) {
+ if (!this->attached()) {
+ ASSERT(0);
+ return;
+ }
+
+ pulseWidth = constrain(pulseWidth, this->minPW, this->maxPW);
+ pwmWrite(this->pin, US_TO_COMPARE(pulseWidth));
+}
+
+uint16 Servo::readMicroseconds() const {
+ if (!this->attached()) {
+ ASSERT(0);
+ return 0;
+ }
+
+ stm32_pin_info pin_info = PIN_MAP[this->pin];
+ uint16 compare = timer_get_compare(pin_info.timer_device,
+ pin_info.timer_channel);
+
+ return COMPARE_TO_US(compare);
+}
+
+void Servo::resetFields(void) {
+ this->pin = NOT_ATTACHED;
+ this->minAngle = SERVO_DEFAULT_MIN_ANGLE;
+ this->maxAngle = SERVO_DEFAULT_MAX_ANGLE;
+ this->minPW = SERVO_DEFAULT_MIN_PW;
+ this->maxPW = SERVO_DEFAULT_MAX_PW;
+}
diff --git a/libraries/Servo/Servo.h b/libraries/Servo/Servo.h
new file mode 100644
index 0000000..94e1e00
--- /dev/null
+++ b/libraries/Servo/Servo.h
@@ -0,0 +1,196 @@
+/******************************************************************************
+ * The MIT License
+ *
+ * Copyright (c) 2010, LeafLabs, LLC.
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy,
+ * modify, merge, publish, distribute, sublicense, and/or sell copies
+ * of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *****************************************************************************/
+
+#ifndef _SERVO_H_
+#define _SERVO_H_
+
+#include <libmaple/libmaple_types.h>
+#include <libmaple/timer.h>
+
+#include <wirish/wirish_types.h>
+
+/*
+ * Note on Arduino compatibility:
+ *
+ * In the Arduino implementation, PWM is done "by hand" in the sense
+ * that timer channels are hijacked in groups and an ISR is set which
+ * toggles Servo::attach()ed pins using digitalWrite().
+ *
+ * While this scheme allows any pin to drive a servo, it chews up
+ * cycles and complicates the programmer's notion of when a particular
+ * timer channel will be in use.
+ *
+ * This implementation only allows Servo instances to attach() to pins
+ * that already have a timer channel associated with them, and just
+ * uses pwmWrite() to drive the wave.
+ *
+ * This introduces an incompatibility: while the Arduino
+ * implementation of attach() returns the affected channel on success
+ * and 0 on failure, this one returns true on success and false on
+ * failure.
+ *
+ * RC Servos expect a pulse every 20ms. Since periods are set for
+ * entire timers, rather than individual channels, attach()ing a Servo
+ * to a pin can interfere with other pins associated with the same
+ * timer. As always, your board's pin map is your friend.
+ */
+
+// Pin number of unattached pins
+#define NOT_ATTACHED (-1)
+
+// Default min/max pulse widths (in microseconds) and angles (in
+// degrees). Values chosen for Arduino compatibility. These values
+// are part of the public API; DO NOT CHANGE THEM.
+#define SERVO_DEFAULT_MIN_PW 544
+#define SERVO_DEFAULT_MAX_PW 2400
+#define SERVO_DEFAULT_MIN_ANGLE 0
+#define SERVO_DEFAULT_MAX_ANGLE 180
+
+/** Class for interfacing with RC servomotors. */
+class Servo {
+public:
+ /**
+ * @brief Construct a new Servo instance.
+ *
+ * The new instance will not be attached to any pin.
+ */
+ Servo();
+
+ /**
+ * @brief Associate this instance with a servomotor whose input is
+ * connected to pin.
+ *
+ * If this instance is already attached to a pin, it will be
+ * detached before being attached to the new pin. This function
+ * doesn't detach any interrupt attached with the pin's timer
+ * channel.
+ *
+ * @param pin Pin connected to the servo pulse wave input. This
+ * pin must be capable of PWM output.
+ *
+ * @param minPulseWidth Minimum pulse width to write to pin, in
+ * microseconds. This will be associated
+ * with a minAngle degree angle. Defaults to
+ * SERVO_DEFAULT_MIN_PW = 544.
+ *
+ * @param maxPulseWidth Maximum pulse width to write to pin, in
+ * microseconds. This will be associated
+ * with a maxAngle degree angle. Defaults to
+ * SERVO_DEFAULT_MAX_PW = 2400.
+ *
+ * @param minAngle Target angle (in degrees) associated with
+ * minPulseWidth. Defaults to
+ * SERVO_DEFAULT_MIN_ANGLE = 0.
+ *
+ * @param maxAngle Target angle (in degrees) associated with
+ * maxPulseWidth. Defaults to
+ * SERVO_DEFAULT_MAX_ANGLE = 180.
+ *
+ * @sideeffect May set pinMode(pin, PWM).
+ *
+ * @return true if successful, false when pin doesn't support PWM.
+ */
+ bool attach(uint8 pin,
+ uint16 minPulseWidth=SERVO_DEFAULT_MIN_PW,
+ uint16 maxPulseWidth=SERVO_DEFAULT_MAX_PW,
+ int16 minAngle=SERVO_DEFAULT_MIN_ANGLE,
+ int16 maxAngle=SERVO_DEFAULT_MAX_ANGLE);
+
+ /**
+ * @brief Check if this instance is attached to a servo.
+ * @return true if this instance is attached to a servo, false otherwise.
+ * @see Servo::attachedPin()
+ */
+ bool attached() const { return this->pin != NOT_ATTACHED; }
+
+ /**
+ * @brief Get the pin this instance is attached to.
+ * @return Pin number if currently attached to a pin, NOT_ATTACHED
+ * otherwise.
+ * @see Servo::attach()
+ */
+ int attachedPin() const { return this->pin; }
+
+ /**
+ * @brief Stop driving the servo pulse train.
+ *
+ * If not currently attached to a motor, this function has no effect.
+ *
+ * @return true if this call did anything, false otherwise.
+ */
+ bool detach();
+
+ /**
+ * @brief Set the servomotor target angle.
+ *
+ * @param angle Target angle, in degrees. If the target angle is
+ * outside the range specified at attach() time, it
+ * will be clamped to lie in that range.
+ *
+ * @see Servo::attach()
+ */
+ void write(int angle);
+
+
+ /**
+ * Get the servomotor's target angle, in degrees. This will
+ * lie inside the range specified at attach() time.
+ *
+ * @see Servo::attach()
+ */
+ int read() const;
+
+ /**
+ * @brief Set the pulse width, in microseconds.
+ *
+ * @param pulseWidth Pulse width to send to the servomotor, in
+ * microseconds. If outside of the range
+ * specified at attach() time, it is clamped to
+ * lie in that range.
+ *
+ * @see Servo::attach()
+ */
+ void writeMicroseconds(uint16 pulseWidth);
+
+ /**
+ * Get the current pulse width, in microseconds. This will
+ * lie within the range specified at attach() time.
+ *
+ * @see Servo::attach()
+ */
+ uint16 readMicroseconds() const;
+
+private:
+ int16 pin;
+ uint16 minPW;
+ uint16 maxPW;
+ int16 minAngle;
+ int16 maxAngle;
+
+ void resetFields(void);
+};
+
+#endif /* _SERVO_H_ */
diff --git a/libraries/Servo/rules.mk b/libraries/Servo/rules.mk
new file mode 100644
index 0000000..e013754
--- /dev/null
+++ b/libraries/Servo/rules.mk
@@ -0,0 +1,29 @@
+# Standard things
+sp := $(sp).x
+dirstack_$(sp) := $(d)
+d := $(dir)
+BUILDDIRS += $(BUILD_PATH)/$(d)
+
+# Local flags
+CXXFLAGS_$(d) := $(WIRISH_INCLUDES) $(LIBMAPLE_INCLUDES)
+
+# Local rules and targets
+cSRCS_$(d) :=
+
+cppSRCS_$(d) := Servo.cpp
+
+cFILES_$(d) := $(cSRCS_$(d):%=$(d)/%)
+cppFILES_$(d) := $(cppSRCS_$(d):%=$(d)/%)
+
+OBJS_$(d) := $(cFILES_$(d):%.c=$(BUILD_PATH)/%.o) \
+ $(cppFILES_$(d):%.cpp=$(BUILD_PATH)/%.o)
+DEPS_$(d) := $(OBJS_$(d):%.o=%.d)
+
+$(OBJS_$(d)): TGT_CXXFLAGS := $(CXXFLAGS_$(d))
+
+TGT_BIN += $(OBJS_$(d))
+
+# Standard things
+-include $(DEPS_$(d))
+d := $(dirstack_$(sp))
+sp := $(basename $(sp)) \ No newline at end of file
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-23 14:35:46 +0000