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targets/TARGET_Maxim/TARGET_MAX32625/pwmout_api.c@0:b74591d5ab33, 2017-12-11 (annotated)

Committer:
be_bryan
Date:
Mon Dec 11 17:54:04 2017 +0000
Revision:
0:b74591d5ab33
motor ++

Who changed what in which revision?

UserRevisionLine numberNew contents of line
be_bryan 0:b74591d5ab33 1 /*******************************************************************************
be_bryan 0:b74591d5ab33 2 * Copyright (c) 2016 Maxim Integrated Products, Inc., All Rights Reserved.
be_bryan 0:b74591d5ab33 3 *
be_bryan 0:b74591d5ab33 4 * Permission is hereby granted, free of charge, to any person obtaining a
be_bryan 0:b74591d5ab33 5 * copy of this software and associated documentation files (the "Software"),
be_bryan 0:b74591d5ab33 6 * to deal in the Software without restriction, including without limitation
be_bryan 0:b74591d5ab33 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
be_bryan 0:b74591d5ab33 8 * and/or sell copies of the Software, and to permit persons to whom the
be_bryan 0:b74591d5ab33 9 * Software is furnished to do so, subject to the following conditions:
be_bryan 0:b74591d5ab33 10 *
be_bryan 0:b74591d5ab33 11 * The above copyright notice and this permission notice shall be included
be_bryan 0:b74591d5ab33 12 * in all copies or substantial portions of the Software.
be_bryan 0:b74591d5ab33 13 *
be_bryan 0:b74591d5ab33 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
be_bryan 0:b74591d5ab33 15 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
be_bryan 0:b74591d5ab33 16 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
be_bryan 0:b74591d5ab33 17 * IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES
be_bryan 0:b74591d5ab33 18 * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
be_bryan 0:b74591d5ab33 19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
be_bryan 0:b74591d5ab33 20 * OTHER DEALINGS IN THE SOFTWARE.
be_bryan 0:b74591d5ab33 21 *
be_bryan 0:b74591d5ab33 22 * Except as contained in this notice, the name of Maxim Integrated
be_bryan 0:b74591d5ab33 23 * Products, Inc. shall not be used except as stated in the Maxim Integrated
be_bryan 0:b74591d5ab33 24 * Products, Inc. Branding Policy.
be_bryan 0:b74591d5ab33 25 *
be_bryan 0:b74591d5ab33 26 * The mere transfer of this software does not imply any licenses
be_bryan 0:b74591d5ab33 27 * of trade secrets, proprietary technology, copyrights, patents,
be_bryan 0:b74591d5ab33 28 * trademarks, maskwork rights, or any other form of intellectual
be_bryan 0:b74591d5ab33 29 * property whatsoever. Maxim Integrated Products, Inc. retains all
be_bryan 0:b74591d5ab33 30 * ownership rights.
be_bryan 0:b74591d5ab33 31 *******************************************************************************
be_bryan 0:b74591d5ab33 32 */
be_bryan 0:b74591d5ab33 33
be_bryan 0:b74591d5ab33 34 #include "mbed_assert.h"
be_bryan 0:b74591d5ab33 35 #include "cmsis.h"
be_bryan 0:b74591d5ab33 36 #include "pwmout_api.h"
be_bryan 0:b74591d5ab33 37 #include "pinmap.h"
be_bryan 0:b74591d5ab33 38 #include "clkman_regs.h"
be_bryan 0:b74591d5ab33 39 #include "PeripheralPins.h"
be_bryan 0:b74591d5ab33 40
be_bryan 0:b74591d5ab33 41 #define MXC_GPIO_OUT_MODE_FIELD_WIDTH 4
be_bryan 0:b74591d5ab33 42 #define MXC_GPIO_OUT_MODE_FIELD_MASK ((uint32_t)0xFFFFFFFF >> (32 - MXC_GPIO_OUT_MODE_FIELD_WIDTH))
be_bryan 0:b74591d5ab33 43 #define MXC_GPIO_FUNC_SEL_FIELD_WIDTH 4
be_bryan 0:b74591d5ab33 44 #define MXC_GPIO_FUNC_SEL_FIELD_MASK ((uint32_t)0xFFFFFFFF >> (32 - MXC_GPIO_FUNC_SEL_FIELD_WIDTH))
be_bryan 0:b74591d5ab33 45
be_bryan 0:b74591d5ab33 46
be_bryan 0:b74591d5ab33 47 //******************************************************************************
be_bryan 0:b74591d5ab33 48 void pwmout_init(pwmout_t* obj, PinName pin)
be_bryan 0:b74591d5ab33 49 {
be_bryan 0:b74591d5ab33 50 // Make sure the pin is free for GPIO use
be_bryan 0:b74591d5ab33 51 unsigned int port = (unsigned int)pin >> PORT_SHIFT;
be_bryan 0:b74591d5ab33 52 unsigned int port_pin = (unsigned int)pin & ~(0xFFFFFFFF << PORT_SHIFT);
be_bryan 0:b74591d5ab33 53 MBED_ASSERT(MXC_GPIO->free[port] & (0x1 << port_pin));
be_bryan 0:b74591d5ab33 54
be_bryan 0:b74591d5ab33 55 int i = 0;
be_bryan 0:b74591d5ab33 56 PinMap pwm = PinMap_PWM[0];
be_bryan 0:b74591d5ab33 57
be_bryan 0:b74591d5ab33 58 // Check if there is a pulse train already active on this port
be_bryan 0:b74591d5ab33 59 int pin_func = (MXC_GPIO->func_sel[port] & (MXC_GPIO_FUNC_SEL_FIELD_MASK << (port_pin * MXC_GPIO_FUNC_SEL_FIELD_WIDTH))) >>
be_bryan 0:b74591d5ab33 60 (port_pin * MXC_GPIO_FUNC_SEL_FIELD_WIDTH);
be_bryan 0:b74591d5ab33 61 MBED_ASSERT((pin_func < 1) || (pin_func > 3));
be_bryan 0:b74591d5ab33 62
be_bryan 0:b74591d5ab33 63 // Search through PinMap_PWM to find the pin
be_bryan 0:b74591d5ab33 64 while (pwm.pin != pin) {
be_bryan 0:b74591d5ab33 65 pwm = PinMap_PWM[++i];
be_bryan 0:b74591d5ab33 66 }
be_bryan 0:b74591d5ab33 67
be_bryan 0:b74591d5ab33 68 // Find a free PT instance on this pin
be_bryan 0:b74591d5ab33 69 while (pwm.pin == pin) {
be_bryan 0:b74591d5ab33 70
be_bryan 0:b74591d5ab33 71 // Check to see if this PT instance is free
be_bryan 0:b74591d5ab33 72 if (((mxc_pt_regs_t*)pwm.peripheral)->rate_length & MXC_F_PT_RATE_LENGTH_MODE) {
be_bryan 0:b74591d5ab33 73 break;
be_bryan 0:b74591d5ab33 74 }
be_bryan 0:b74591d5ab33 75
be_bryan 0:b74591d5ab33 76 pwm = PinMap_PWM[++i];
be_bryan 0:b74591d5ab33 77
be_bryan 0:b74591d5ab33 78 // Raise an assertion if we can not allocate another PT instance.
be_bryan 0:b74591d5ab33 79 MBED_ASSERT(pwm.pin == pin);
be_bryan 0:b74591d5ab33 80 }
be_bryan 0:b74591d5ab33 81
be_bryan 0:b74591d5ab33 82 // Enable the clock
be_bryan 0:b74591d5ab33 83 MXC_CLKMAN->sys_clk_ctrl_7_pt = MXC_S_CLKMAN_CLK_SCALE_DIV_1;
be_bryan 0:b74591d5ab33 84
be_bryan 0:b74591d5ab33 85 // Set the obj pointer to the propper PWM instance
be_bryan 0:b74591d5ab33 86 obj->pwm = (mxc_pt_regs_t*)pwm.peripheral;
be_bryan 0:b74591d5ab33 87
be_bryan 0:b74591d5ab33 88 // Initialize object period and pulse width
be_bryan 0:b74591d5ab33 89 obj->period = -1;
be_bryan 0:b74591d5ab33 90 obj->pulse_width = -1;
be_bryan 0:b74591d5ab33 91
be_bryan 0:b74591d5ab33 92 // Disable the output
be_bryan 0:b74591d5ab33 93 obj->pwm->train = 0x0;
be_bryan 0:b74591d5ab33 94 obj->pwm->rate_length = 0x0;
be_bryan 0:b74591d5ab33 95
be_bryan 0:b74591d5ab33 96 // Configure the pin
be_bryan 0:b74591d5ab33 97 pin_mode(pin, (PinMode)PullNone);
be_bryan 0:b74591d5ab33 98 pin_function(pin, pwm.function);
be_bryan 0:b74591d5ab33 99
be_bryan 0:b74591d5ab33 100 // default to 20ms: standard for servos, and fine for e.g. brightness control
be_bryan 0:b74591d5ab33 101 pwmout_period_us(obj, 20000);
be_bryan 0:b74591d5ab33 102 pwmout_write (obj, 0);
be_bryan 0:b74591d5ab33 103
be_bryan 0:b74591d5ab33 104 // Set the drive mode to normal
be_bryan 0:b74591d5ab33 105 MXC_SET_FIELD(&MXC_GPIO->out_mode[port],
be_bryan 0:b74591d5ab33 106 (MXC_GPIO_OUT_MODE_FIELD_MASK << (port_pin * MXC_GPIO_OUT_MODE_FIELD_WIDTH)),
be_bryan 0:b74591d5ab33 107 (MXC_V_GPIO_OUT_MODE_NORMAL << (port_pin * MXC_GPIO_OUT_MODE_FIELD_WIDTH)));
be_bryan 0:b74591d5ab33 108
be_bryan 0:b74591d5ab33 109 // Enable this PWM channel
be_bryan 0:b74591d5ab33 110 MXC_PTG->enable |= (1 << MXC_PT_GET_IDX(obj->pwm));
be_bryan 0:b74591d5ab33 111 }
be_bryan 0:b74591d5ab33 112
be_bryan 0:b74591d5ab33 113 //******************************************************************************
be_bryan 0:b74591d5ab33 114 void pwmout_free(pwmout_t* obj)
be_bryan 0:b74591d5ab33 115 {
be_bryan 0:b74591d5ab33 116 // Set the registers to the reset value
be_bryan 0:b74591d5ab33 117 obj->pwm->train = 0;
be_bryan 0:b74591d5ab33 118 obj->pwm->rate_length = 0x08000000;
be_bryan 0:b74591d5ab33 119 }
be_bryan 0:b74591d5ab33 120
be_bryan 0:b74591d5ab33 121 //******************************************************************************
be_bryan 0:b74591d5ab33 122 static void pwmout_update(pwmout_t* obj)
be_bryan 0:b74591d5ab33 123 {
be_bryan 0:b74591d5ab33 124 // Calculate and set the divider ratio
be_bryan 0:b74591d5ab33 125 int div = (obj->period * (SystemCoreClock / 1000000))/32;
be_bryan 0:b74591d5ab33 126 if (div < 2) {
be_bryan 0:b74591d5ab33 127 div = 2;
be_bryan 0:b74591d5ab33 128 }
be_bryan 0:b74591d5ab33 129 MXC_SET_FIELD(&obj->pwm->rate_length, MXC_F_PT_RATE_LENGTH_RATE_CONTROL, div);
be_bryan 0:b74591d5ab33 130
be_bryan 0:b74591d5ab33 131 // Change the duty cycle to adjust the pulse width
be_bryan 0:b74591d5ab33 132 obj->pwm->train = (0xFFFFFFFF << (32 - ((32 * obj->pulse_width) / obj->period)));
be_bryan 0:b74591d5ab33 133 }
be_bryan 0:b74591d5ab33 134
be_bryan 0:b74591d5ab33 135
be_bryan 0:b74591d5ab33 136 //******************************************************************************
be_bryan 0:b74591d5ab33 137 void pwmout_write(pwmout_t* obj, float percent)
be_bryan 0:b74591d5ab33 138 {
be_bryan 0:b74591d5ab33 139 // Saturate percent if outside of range
be_bryan 0:b74591d5ab33 140 if(percent < 0.0f) {
be_bryan 0:b74591d5ab33 141 percent = 0.0f;
be_bryan 0:b74591d5ab33 142 } else if(percent > 1.0f) {
be_bryan 0:b74591d5ab33 143 percent = 1.0f;
be_bryan 0:b74591d5ab33 144 }
be_bryan 0:b74591d5ab33 145
be_bryan 0:b74591d5ab33 146 // Resize the pulse width to set the duty cycle
be_bryan 0:b74591d5ab33 147 pwmout_pulsewidth_us(obj, (int)(percent*obj->period));
be_bryan 0:b74591d5ab33 148 }
be_bryan 0:b74591d5ab33 149
be_bryan 0:b74591d5ab33 150 //******************************************************************************
be_bryan 0:b74591d5ab33 151 float pwmout_read(pwmout_t* obj)
be_bryan 0:b74591d5ab33 152 {
be_bryan 0:b74591d5ab33 153 // Check for when pulsewidth or period equals 0
be_bryan 0:b74591d5ab33 154 if((obj->pulse_width == 0) || (obj->period == 0)) {
be_bryan 0:b74591d5ab33 155 return 0;
be_bryan 0:b74591d5ab33 156 }
be_bryan 0:b74591d5ab33 157
be_bryan 0:b74591d5ab33 158 // Return the duty cycle
be_bryan 0:b74591d5ab33 159 return ((float)obj->pulse_width / (float)obj->period);
be_bryan 0:b74591d5ab33 160 }
be_bryan 0:b74591d5ab33 161
be_bryan 0:b74591d5ab33 162 //******************************************************************************
be_bryan 0:b74591d5ab33 163 void pwmout_period(pwmout_t* obj, float seconds)
be_bryan 0:b74591d5ab33 164 {
be_bryan 0:b74591d5ab33 165 pwmout_period_us(obj, (int)(seconds * 1000000.0f));
be_bryan 0:b74591d5ab33 166 }
be_bryan 0:b74591d5ab33 167
be_bryan 0:b74591d5ab33 168 //******************************************************************************
be_bryan 0:b74591d5ab33 169 void pwmout_period_ms(pwmout_t* obj, int ms)
be_bryan 0:b74591d5ab33 170 {
be_bryan 0:b74591d5ab33 171 pwmout_period_us(obj, ms * 1000);
be_bryan 0:b74591d5ab33 172 }
be_bryan 0:b74591d5ab33 173
be_bryan 0:b74591d5ab33 174 //******************************************************************************
be_bryan 0:b74591d5ab33 175 void pwmout_period_us(pwmout_t* obj, int us)
be_bryan 0:b74591d5ab33 176 {
be_bryan 0:b74591d5ab33 177 // Check the range of the period
be_bryan 0:b74591d5ab33 178 MBED_ASSERT((us >= 0) && (us <= (int)(SystemCoreClock / 32)));
be_bryan 0:b74591d5ab33 179
be_bryan 0:b74591d5ab33 180 // Set pulse width to half the period if uninitialized
be_bryan 0:b74591d5ab33 181 if (obj->pulse_width == -1) {
be_bryan 0:b74591d5ab33 182 obj->pulse_width = us / 2;
be_bryan 0:b74591d5ab33 183 }
be_bryan 0:b74591d5ab33 184
be_bryan 0:b74591d5ab33 185 // Save the period
be_bryan 0:b74591d5ab33 186 obj->period = us;
be_bryan 0:b74591d5ab33 187
be_bryan 0:b74591d5ab33 188 // Update the registers
be_bryan 0:b74591d5ab33 189 pwmout_update(obj);
be_bryan 0:b74591d5ab33 190 }
be_bryan 0:b74591d5ab33 191
be_bryan 0:b74591d5ab33 192 //******************************************************************************
be_bryan 0:b74591d5ab33 193 void pwmout_pulsewidth(pwmout_t* obj, float seconds)
be_bryan 0:b74591d5ab33 194 {
be_bryan 0:b74591d5ab33 195 pwmout_pulsewidth_us(obj, (int)(seconds * 1000000.0f));
be_bryan 0:b74591d5ab33 196 }
be_bryan 0:b74591d5ab33 197
be_bryan 0:b74591d5ab33 198 //******************************************************************************
be_bryan 0:b74591d5ab33 199 void pwmout_pulsewidth_ms(pwmout_t* obj, int ms)
be_bryan 0:b74591d5ab33 200 {
be_bryan 0:b74591d5ab33 201 pwmout_pulsewidth_us(obj, ms * 1000);
be_bryan 0:b74591d5ab33 202 }
be_bryan 0:b74591d5ab33 203
be_bryan 0:b74591d5ab33 204 //******************************************************************************
be_bryan 0:b74591d5ab33 205 void pwmout_pulsewidth_us(pwmout_t* obj, int us)
be_bryan 0:b74591d5ab33 206 {
be_bryan 0:b74591d5ab33 207 // Check the range of the pulsewidth
be_bryan 0:b74591d5ab33 208 MBED_ASSERT((us >= 0) && (us <= (int)(SystemCoreClock / 32)));
be_bryan 0:b74591d5ab33 209
be_bryan 0:b74591d5ab33 210 // Initialize period to double the pulsewidth if uninitialized
be_bryan 0:b74591d5ab33 211 if (obj->period == -1) {
be_bryan 0:b74591d5ab33 212 obj->period = 2 * us;
be_bryan 0:b74591d5ab33 213 }
be_bryan 0:b74591d5ab33 214
be_bryan 0:b74591d5ab33 215 // Save the pulsewidth
be_bryan 0:b74591d5ab33 216 obj->pulse_width = us;
be_bryan 0:b74591d5ab33 217
be_bryan 0:b74591d5ab33 218 // Update the register
be_bryan 0:b74591d5ab33 219 pwmout_update(obj);
be_bryan 0:b74591d5ab33 220 }
be_bryan 0:b74591d5ab33 221