MacroRat / MouseCode

Important changes to repositories hosted on mbed.com

Mbed hosted mercurial repositories are deprecated and are due to be permanently deleted in July 2026.

To keep a copy of this software download the repository Zip archive or clone locally using Mercurial.

It is also possible to export all your personal repositories from the account settings page.

Dependencies:   ITG3200 QEI

mbed-dev/targets/TARGET_Maxim/TARGET_MAX32620/pwmout_api.c@18:6a4db94011d3, 2017-05-14 (annotated)

Committer:
sahilmgandhi
Date:
Sun May 14 23:18:57 2017 +0000
Revision:
18:6a4db94011d3
Publishing again

Who changed what in which revision?

UserRevisionLine numberNew contents of line
sahilmgandhi 18:6a4db94011d3 1 /*******************************************************************************
sahilmgandhi 18:6a4db94011d3 2 * Copyright (C) 2016 Maxim Integrated Products, Inc., All Rights Reserved.
sahilmgandhi 18:6a4db94011d3 3 *
sahilmgandhi 18:6a4db94011d3 4 * Permission is hereby granted, free of charge, to any person obtaining a
sahilmgandhi 18:6a4db94011d3 5 * copy of this software and associated documentation files (the "Software"),
sahilmgandhi 18:6a4db94011d3 6 * to deal in the Software without restriction, including without limitation
sahilmgandhi 18:6a4db94011d3 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
sahilmgandhi 18:6a4db94011d3 8 * and/or sell copies of the Software, and to permit persons to whom the
sahilmgandhi 18:6a4db94011d3 9 * Software is furnished to do so, subject to the following conditions:
sahilmgandhi 18:6a4db94011d3 10 *
sahilmgandhi 18:6a4db94011d3 11 * The above copyright notice and this permission notice shall be included
sahilmgandhi 18:6a4db94011d3 12 * in all copies or substantial portions of the Software.
sahilmgandhi 18:6a4db94011d3 13 *
sahilmgandhi 18:6a4db94011d3 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
sahilmgandhi 18:6a4db94011d3 15 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
sahilmgandhi 18:6a4db94011d3 16 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
sahilmgandhi 18:6a4db94011d3 17 * IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES
sahilmgandhi 18:6a4db94011d3 18 * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
sahilmgandhi 18:6a4db94011d3 19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
sahilmgandhi 18:6a4db94011d3 20 * OTHER DEALINGS IN THE SOFTWARE.
sahilmgandhi 18:6a4db94011d3 21 *
sahilmgandhi 18:6a4db94011d3 22 * Except as contained in this notice, the name of Maxim Integrated
sahilmgandhi 18:6a4db94011d3 23 * Products, Inc. shall not be used except as stated in the Maxim Integrated
sahilmgandhi 18:6a4db94011d3 24 * Products, Inc. Branding Policy.
sahilmgandhi 18:6a4db94011d3 25 *
sahilmgandhi 18:6a4db94011d3 26 * The mere transfer of this software does not imply any licenses
sahilmgandhi 18:6a4db94011d3 27 * of trade secrets, proprietary technology, copyrights, patents,
sahilmgandhi 18:6a4db94011d3 28 * trademarks, maskwork rights, or any other form of intellectual
sahilmgandhi 18:6a4db94011d3 29 * property whatsoever. Maxim Integrated Products, Inc. retains all
sahilmgandhi 18:6a4db94011d3 30 * ownership rights.
sahilmgandhi 18:6a4db94011d3 31 *******************************************************************************
sahilmgandhi 18:6a4db94011d3 32 */
sahilmgandhi 18:6a4db94011d3 33
sahilmgandhi 18:6a4db94011d3 34 #include "mbed_assert.h"
sahilmgandhi 18:6a4db94011d3 35 #include "cmsis.h"
sahilmgandhi 18:6a4db94011d3 36 #include "pwmout_api.h"
sahilmgandhi 18:6a4db94011d3 37 #include "pinmap.h"
sahilmgandhi 18:6a4db94011d3 38 #include "clkman_regs.h"
sahilmgandhi 18:6a4db94011d3 39 #include "PeripheralPins.h"
sahilmgandhi 18:6a4db94011d3 40
sahilmgandhi 18:6a4db94011d3 41 //******************************************************************************
sahilmgandhi 18:6a4db94011d3 42 void pwmout_init(pwmout_t* obj, PinName pin)
sahilmgandhi 18:6a4db94011d3 43 {
sahilmgandhi 18:6a4db94011d3 44 // Make sure the pin is free for GPIO use
sahilmgandhi 18:6a4db94011d3 45 unsigned int port = (unsigned int)pin >> PORT_SHIFT;
sahilmgandhi 18:6a4db94011d3 46 unsigned int port_pin = (unsigned int)pin & ~(0xFFFFFFFF << PORT_SHIFT);
sahilmgandhi 18:6a4db94011d3 47 MBED_ASSERT(MXC_GPIO->free[port] & (0x1 << port_pin));
sahilmgandhi 18:6a4db94011d3 48
sahilmgandhi 18:6a4db94011d3 49 int i = 0;
sahilmgandhi 18:6a4db94011d3 50 PinMap pwm = PinMap_PWM[0];
sahilmgandhi 18:6a4db94011d3 51
sahilmgandhi 18:6a4db94011d3 52 // Check if there is a pulse train already active on this port
sahilmgandhi 18:6a4db94011d3 53 int pin_func = (MXC_GPIO->func_sel[port] & (0xF << (port_pin*4))) >> (port_pin*4);
sahilmgandhi 18:6a4db94011d3 54 MBED_ASSERT((pin_func < 1) || (pin_func > 3));
sahilmgandhi 18:6a4db94011d3 55
sahilmgandhi 18:6a4db94011d3 56 // Search through PinMap_PWM to find the pin
sahilmgandhi 18:6a4db94011d3 57 while (pwm.pin != pin) {
sahilmgandhi 18:6a4db94011d3 58 pwm = PinMap_PWM[++i];
sahilmgandhi 18:6a4db94011d3 59 }
sahilmgandhi 18:6a4db94011d3 60
sahilmgandhi 18:6a4db94011d3 61 // Find a free PT instance on this pin
sahilmgandhi 18:6a4db94011d3 62 while (pwm.pin == pin) {
sahilmgandhi 18:6a4db94011d3 63
sahilmgandhi 18:6a4db94011d3 64 // Check to see if this PT instance is free
sahilmgandhi 18:6a4db94011d3 65 if (((mxc_pt_regs_t*)pwm.peripheral)->rate_length & MXC_F_PT_RATE_LENGTH_MODE) {
sahilmgandhi 18:6a4db94011d3 66 break;
sahilmgandhi 18:6a4db94011d3 67 }
sahilmgandhi 18:6a4db94011d3 68
sahilmgandhi 18:6a4db94011d3 69 pwm = PinMap_PWM[++i];
sahilmgandhi 18:6a4db94011d3 70
sahilmgandhi 18:6a4db94011d3 71 // Raise an assertion if we can not allocate another PT instance.
sahilmgandhi 18:6a4db94011d3 72 MBED_ASSERT(pwm.pin == pin);
sahilmgandhi 18:6a4db94011d3 73 }
sahilmgandhi 18:6a4db94011d3 74
sahilmgandhi 18:6a4db94011d3 75 // Enable the clock
sahilmgandhi 18:6a4db94011d3 76 MXC_CLKMAN->sys_clk_ctrl_7_pt = MXC_S_CLKMAN_CLK_SCALE_DIV_1;
sahilmgandhi 18:6a4db94011d3 77
sahilmgandhi 18:6a4db94011d3 78 // Set the obj pointer to the propper PWM instance
sahilmgandhi 18:6a4db94011d3 79 obj->pwm = (mxc_pt_regs_t*)pwm.peripheral;
sahilmgandhi 18:6a4db94011d3 80
sahilmgandhi 18:6a4db94011d3 81 // Initialize object period and pulse width
sahilmgandhi 18:6a4db94011d3 82 obj->period = -1;
sahilmgandhi 18:6a4db94011d3 83 obj->pulse_width = -1;
sahilmgandhi 18:6a4db94011d3 84
sahilmgandhi 18:6a4db94011d3 85 // Disable the output
sahilmgandhi 18:6a4db94011d3 86 obj->pwm->train = 0x0;
sahilmgandhi 18:6a4db94011d3 87 obj->pwm->rate_length = 0x0;
sahilmgandhi 18:6a4db94011d3 88
sahilmgandhi 18:6a4db94011d3 89 // Configure the pin
sahilmgandhi 18:6a4db94011d3 90 pin_mode(pin, (PinMode)PullNone);
sahilmgandhi 18:6a4db94011d3 91 pin_function(pin, pwm.function);
sahilmgandhi 18:6a4db94011d3 92
sahilmgandhi 18:6a4db94011d3 93 // default to 20ms: standard for servos, and fine for e.g. brightness control
sahilmgandhi 18:6a4db94011d3 94 pwmout_period_us(obj, 20000);
sahilmgandhi 18:6a4db94011d3 95 pwmout_write (obj, 0);
sahilmgandhi 18:6a4db94011d3 96
sahilmgandhi 18:6a4db94011d3 97 // Set the drive mode to normal
sahilmgandhi 18:6a4db94011d3 98 MXC_SET_FIELD(&MXC_GPIO->out_mode[port], (0x7 << (port_pin*4)), (MXC_V_GPIO_OUT_MODE_NORMAL << (port_pin*4)));
sahilmgandhi 18:6a4db94011d3 99
sahilmgandhi 18:6a4db94011d3 100 // Enable this PWM channel
sahilmgandhi 18:6a4db94011d3 101 MXC_PTG->enable |= (1 << MXC_PT_GET_IDX(obj->pwm));
sahilmgandhi 18:6a4db94011d3 102 }
sahilmgandhi 18:6a4db94011d3 103
sahilmgandhi 18:6a4db94011d3 104 //******************************************************************************
sahilmgandhi 18:6a4db94011d3 105 void pwmout_free(pwmout_t* obj)
sahilmgandhi 18:6a4db94011d3 106 {
sahilmgandhi 18:6a4db94011d3 107 // Set the registers to the reset value
sahilmgandhi 18:6a4db94011d3 108 obj->pwm->train = 0;
sahilmgandhi 18:6a4db94011d3 109 obj->pwm->rate_length = 0x08000000;
sahilmgandhi 18:6a4db94011d3 110 }
sahilmgandhi 18:6a4db94011d3 111
sahilmgandhi 18:6a4db94011d3 112 //******************************************************************************
sahilmgandhi 18:6a4db94011d3 113 static void pwmout_update(pwmout_t* obj)
sahilmgandhi 18:6a4db94011d3 114 {
sahilmgandhi 18:6a4db94011d3 115 // Calculate and set the divider ratio
sahilmgandhi 18:6a4db94011d3 116 int div = (obj->period * (SystemCoreClock/1000000))/32;
sahilmgandhi 18:6a4db94011d3 117 if (div < 2) {
sahilmgandhi 18:6a4db94011d3 118 div = 2;
sahilmgandhi 18:6a4db94011d3 119 }
sahilmgandhi 18:6a4db94011d3 120 MXC_SET_FIELD(&obj->pwm->rate_length, MXC_F_PT_RATE_LENGTH_RATE_CONTROL, div);
sahilmgandhi 18:6a4db94011d3 121
sahilmgandhi 18:6a4db94011d3 122 // Change the duty cycle to adjust the pulse width
sahilmgandhi 18:6a4db94011d3 123 obj->pwm->train = (0xFFFFFFFF << (32-((32*obj->pulse_width)/obj->period)));
sahilmgandhi 18:6a4db94011d3 124 }
sahilmgandhi 18:6a4db94011d3 125
sahilmgandhi 18:6a4db94011d3 126
sahilmgandhi 18:6a4db94011d3 127 //******************************************************************************
sahilmgandhi 18:6a4db94011d3 128 void pwmout_write(pwmout_t* obj, float percent)
sahilmgandhi 18:6a4db94011d3 129 {
sahilmgandhi 18:6a4db94011d3 130 // Saturate percent if outside of range
sahilmgandhi 18:6a4db94011d3 131 if (percent < 0.0f) {
sahilmgandhi 18:6a4db94011d3 132 percent = 0.0f;
sahilmgandhi 18:6a4db94011d3 133 } else if(percent > 1.0f) {
sahilmgandhi 18:6a4db94011d3 134 percent = 1.0f;
sahilmgandhi 18:6a4db94011d3 135 }
sahilmgandhi 18:6a4db94011d3 136
sahilmgandhi 18:6a4db94011d3 137 // Resize the pulse width to set the duty cycle
sahilmgandhi 18:6a4db94011d3 138 pwmout_pulsewidth_us(obj, (int)(percent*obj->period));
sahilmgandhi 18:6a4db94011d3 139 }
sahilmgandhi 18:6a4db94011d3 140
sahilmgandhi 18:6a4db94011d3 141 //******************************************************************************
sahilmgandhi 18:6a4db94011d3 142 float pwmout_read(pwmout_t* obj)
sahilmgandhi 18:6a4db94011d3 143 {
sahilmgandhi 18:6a4db94011d3 144 // Check for when pulsewidth or period equals 0
sahilmgandhi 18:6a4db94011d3 145 if ((obj->pulse_width == 0) || (obj->period == 0)) {
sahilmgandhi 18:6a4db94011d3 146 return 0;
sahilmgandhi 18:6a4db94011d3 147 }
sahilmgandhi 18:6a4db94011d3 148
sahilmgandhi 18:6a4db94011d3 149 // Return the duty cycle
sahilmgandhi 18:6a4db94011d3 150 return ((float)obj->pulse_width / (float)obj->period);
sahilmgandhi 18:6a4db94011d3 151 }
sahilmgandhi 18:6a4db94011d3 152
sahilmgandhi 18:6a4db94011d3 153 //******************************************************************************
sahilmgandhi 18:6a4db94011d3 154 void pwmout_period(pwmout_t* obj, float seconds)
sahilmgandhi 18:6a4db94011d3 155 {
sahilmgandhi 18:6a4db94011d3 156 pwmout_period_us(obj, (int)(seconds * 1000000.0f));
sahilmgandhi 18:6a4db94011d3 157 }
sahilmgandhi 18:6a4db94011d3 158
sahilmgandhi 18:6a4db94011d3 159 //******************************************************************************
sahilmgandhi 18:6a4db94011d3 160 void pwmout_period_ms(pwmout_t* obj, int ms)
sahilmgandhi 18:6a4db94011d3 161 {
sahilmgandhi 18:6a4db94011d3 162 pwmout_period_us(obj, ms*1000);
sahilmgandhi 18:6a4db94011d3 163 }
sahilmgandhi 18:6a4db94011d3 164
sahilmgandhi 18:6a4db94011d3 165 //******************************************************************************
sahilmgandhi 18:6a4db94011d3 166 void pwmout_period_us(pwmout_t* obj, int us)
sahilmgandhi 18:6a4db94011d3 167 {
sahilmgandhi 18:6a4db94011d3 168 // Check the range of the period
sahilmgandhi 18:6a4db94011d3 169 MBED_ASSERT((us >= 0) && (us <= (int)(SystemCoreClock/32)));
sahilmgandhi 18:6a4db94011d3 170
sahilmgandhi 18:6a4db94011d3 171 // Set pulse width to half the period if uninitialized
sahilmgandhi 18:6a4db94011d3 172 if (obj->pulse_width == -1) {
sahilmgandhi 18:6a4db94011d3 173 obj->pulse_width = us/2;
sahilmgandhi 18:6a4db94011d3 174 }
sahilmgandhi 18:6a4db94011d3 175
sahilmgandhi 18:6a4db94011d3 176 // Save the period
sahilmgandhi 18:6a4db94011d3 177 obj->period = us;
sahilmgandhi 18:6a4db94011d3 178
sahilmgandhi 18:6a4db94011d3 179 // Update the registers
sahilmgandhi 18:6a4db94011d3 180 pwmout_update(obj);
sahilmgandhi 18:6a4db94011d3 181 }
sahilmgandhi 18:6a4db94011d3 182
sahilmgandhi 18:6a4db94011d3 183 //******************************************************************************
sahilmgandhi 18:6a4db94011d3 184 void pwmout_pulsewidth(pwmout_t* obj, float seconds)
sahilmgandhi 18:6a4db94011d3 185 {
sahilmgandhi 18:6a4db94011d3 186 pwmout_pulsewidth_us(obj, (int)(seconds * 1000000.0f));
sahilmgandhi 18:6a4db94011d3 187 }
sahilmgandhi 18:6a4db94011d3 188
sahilmgandhi 18:6a4db94011d3 189 //******************************************************************************
sahilmgandhi 18:6a4db94011d3 190 void pwmout_pulsewidth_ms(pwmout_t* obj, int ms)
sahilmgandhi 18:6a4db94011d3 191 {
sahilmgandhi 18:6a4db94011d3 192 pwmout_pulsewidth_us(obj, ms*1000);
sahilmgandhi 18:6a4db94011d3 193 }
sahilmgandhi 18:6a4db94011d3 194
sahilmgandhi 18:6a4db94011d3 195 //******************************************************************************
sahilmgandhi 18:6a4db94011d3 196 void pwmout_pulsewidth_us(pwmout_t* obj, int us)
sahilmgandhi 18:6a4db94011d3 197 {
sahilmgandhi 18:6a4db94011d3 198 // Check the range of the pulsewidth
sahilmgandhi 18:6a4db94011d3 199 MBED_ASSERT((us >= 0) && (us <= (int)(SystemCoreClock/32)));
sahilmgandhi 18:6a4db94011d3 200
sahilmgandhi 18:6a4db94011d3 201 // Initialize period to double the pulsewidth if uninitialized
sahilmgandhi 18:6a4db94011d3 202 if (obj->period == -1) {
sahilmgandhi 18:6a4db94011d3 203 obj->period = 2*us;
sahilmgandhi 18:6a4db94011d3 204 }
sahilmgandhi 18:6a4db94011d3 205
sahilmgandhi 18:6a4db94011d3 206 // Save the pulsewidth
sahilmgandhi 18:6a4db94011d3 207 obj->pulse_width = us;
sahilmgandhi 18:6a4db94011d3 208
sahilmgandhi 18:6a4db94011d3 209 // Update the register
sahilmgandhi 18:6a4db94011d3 210 pwmout_update(obj);
sahilmgandhi 18:6a4db94011d3 211 }