MacroRat / MouseCode

Mouse code for the MacroRat

Dependencies:   ITG3200 QEI

mbed-dev/targets/TARGET_NXP/TARGET_LPC408X/TARGET_LPC4088_DM/pwmout_api.c@46:b156ef445742, 2017-06-03 (annotated)

Committer:
sahilmgandhi
Date:
Sat Jun 03 00:22:44 2017 +0000
Revision:
46:b156ef445742
Parent:
18:6a4db94011d3 
Final code for internal battlebot competition.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
sahilmgandhi 18:6a4db94011d3 1 /* mbed Microcontroller Library
sahilmgandhi 18:6a4db94011d3 2 * Copyright (c) 2006-2013 ARM Limited
sahilmgandhi 18:6a4db94011d3 3 *
sahilmgandhi 18:6a4db94011d3 4 * Licensed under the Apache License, Version 2.0 (the "License");
sahilmgandhi 18:6a4db94011d3 5 * you may not use this file except in compliance with the License.
sahilmgandhi 18:6a4db94011d3 6 * You may obtain a copy of the License at
sahilmgandhi 18:6a4db94011d3 7 *
sahilmgandhi 18:6a4db94011d3 8 * http://www.apache.org/licenses/LICENSE-2.0
sahilmgandhi 18:6a4db94011d3 9 *
sahilmgandhi 18:6a4db94011d3 10 * Unless required by applicable law or agreed to in writing, software
sahilmgandhi 18:6a4db94011d3 11 * distributed under the License is distributed on an "AS IS" BASIS,
sahilmgandhi 18:6a4db94011d3 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
sahilmgandhi 18:6a4db94011d3 13 * See the License for the specific language governing permissions and
sahilmgandhi 18:6a4db94011d3 14 * limitations under the License.
sahilmgandhi 18:6a4db94011d3 15 */
sahilmgandhi 18:6a4db94011d3 16 #include "mbed_assert.h"
sahilmgandhi 18:6a4db94011d3 17 #include "pwmout_api.h"
sahilmgandhi 18:6a4db94011d3 18 #include "cmsis.h"
sahilmgandhi 18:6a4db94011d3 19 #include "pinmap.h"
sahilmgandhi 18:6a4db94011d3 20
sahilmgandhi 18:6a4db94011d3 21 #define TCR_CNT_EN 0x00000001
sahilmgandhi 18:6a4db94011d3 22 #define TCR_RESET 0x00000002
sahilmgandhi 18:6a4db94011d3 23
sahilmgandhi 18:6a4db94011d3 24 // PORT ID, PWM ID, Pin function
sahilmgandhi 18:6a4db94011d3 25 static const PinMap PinMap_PWM[] = {
sahilmgandhi 18:6a4db94011d3 26 {P1_5, PWM0_3, 3},
sahilmgandhi 18:6a4db94011d3 27 {P1_20, PWM1_2, 2},
sahilmgandhi 18:6a4db94011d3 28 {P1_23, PWM1_4, 2},
sahilmgandhi 18:6a4db94011d3 29 {P1_24, PWM1_5, 2},
sahilmgandhi 18:6a4db94011d3 30 {NC, NC, 0}
sahilmgandhi 18:6a4db94011d3 31 };
sahilmgandhi 18:6a4db94011d3 32
sahilmgandhi 18:6a4db94011d3 33 static const uint32_t PWM_mr_offset[7] = {
sahilmgandhi 18:6a4db94011d3 34 0x18, 0x1C, 0x20, 0x24, 0x40, 0x44, 0x48
sahilmgandhi 18:6a4db94011d3 35 };
sahilmgandhi 18:6a4db94011d3 36
sahilmgandhi 18:6a4db94011d3 37 #define TCR_PWM_EN 0x00000008
sahilmgandhi 18:6a4db94011d3 38 static unsigned int pwm_clock_mhz;
sahilmgandhi 18:6a4db94011d3 39
sahilmgandhi 18:6a4db94011d3 40 void pwmout_init(pwmout_t* obj, PinName pin) {
sahilmgandhi 18:6a4db94011d3 41 // determine the channel
sahilmgandhi 18:6a4db94011d3 42 PWMName pwm = (PWMName)pinmap_peripheral(pin, PinMap_PWM);
sahilmgandhi 18:6a4db94011d3 43 MBED_ASSERT(pwm != (PWMName)NC);
sahilmgandhi 18:6a4db94011d3 44
sahilmgandhi 18:6a4db94011d3 45 obj->channel = pwm;
sahilmgandhi 18:6a4db94011d3 46 obj->pwm = LPC_PWM0;
sahilmgandhi 18:6a4db94011d3 47
sahilmgandhi 18:6a4db94011d3 48 if (obj->channel > 6) { // PWM1 is used if pwm > 6
sahilmgandhi 18:6a4db94011d3 49 obj->channel -= 6;
sahilmgandhi 18:6a4db94011d3 50 obj->pwm = LPC_PWM1;
sahilmgandhi 18:6a4db94011d3 51 }
sahilmgandhi 18:6a4db94011d3 52
sahilmgandhi 18:6a4db94011d3 53 obj->MR = (__IO uint32_t *)((uint32_t)obj->pwm + PWM_mr_offset[obj->channel]);
sahilmgandhi 18:6a4db94011d3 54
sahilmgandhi 18:6a4db94011d3 55 // ensure the power is on
sahilmgandhi 18:6a4db94011d3 56 if (obj->pwm == LPC_PWM0) {
sahilmgandhi 18:6a4db94011d3 57 LPC_SC->PCONP |= 1 << 5;
sahilmgandhi 18:6a4db94011d3 58 } else {
sahilmgandhi 18:6a4db94011d3 59 LPC_SC->PCONP |= 1 << 6;
sahilmgandhi 18:6a4db94011d3 60 }
sahilmgandhi 18:6a4db94011d3 61
sahilmgandhi 18:6a4db94011d3 62 obj->pwm->PR = 0; // no pre-scale
sahilmgandhi 18:6a4db94011d3 63
sahilmgandhi 18:6a4db94011d3 64 // ensure single PWM mode
sahilmgandhi 18:6a4db94011d3 65 obj->pwm->MCR = 1 << 1; // reset TC on match 0
sahilmgandhi 18:6a4db94011d3 66
sahilmgandhi 18:6a4db94011d3 67 // enable the specific PWM output
sahilmgandhi 18:6a4db94011d3 68 obj->pwm->PCR |= 1 << (8 + obj->channel);
sahilmgandhi 18:6a4db94011d3 69
sahilmgandhi 18:6a4db94011d3 70 pwm_clock_mhz = PeripheralClock / 1000000;
sahilmgandhi 18:6a4db94011d3 71
sahilmgandhi 18:6a4db94011d3 72 // default to 20ms: standard for servos, and fine for e.g. brightness control
sahilmgandhi 18:6a4db94011d3 73 pwmout_period_ms(obj, 20);
sahilmgandhi 18:6a4db94011d3 74 pwmout_write (obj, 0);
sahilmgandhi 18:6a4db94011d3 75
sahilmgandhi 18:6a4db94011d3 76 // Wire pinout
sahilmgandhi 18:6a4db94011d3 77 pinmap_pinout(pin, PinMap_PWM);
sahilmgandhi 18:6a4db94011d3 78 }
sahilmgandhi 18:6a4db94011d3 79
sahilmgandhi 18:6a4db94011d3 80 void pwmout_free(pwmout_t* obj) {
sahilmgandhi 18:6a4db94011d3 81 // [TODO]
sahilmgandhi 18:6a4db94011d3 82 }
sahilmgandhi 18:6a4db94011d3 83
sahilmgandhi 18:6a4db94011d3 84 void pwmout_write(pwmout_t* obj, float value) {
sahilmgandhi 18:6a4db94011d3 85 if (value < 0.0f) {
sahilmgandhi 18:6a4db94011d3 86 value = 0.0;
sahilmgandhi 18:6a4db94011d3 87 } else if (value > 1.0f) {
sahilmgandhi 18:6a4db94011d3 88 value = 1.0;
sahilmgandhi 18:6a4db94011d3 89 }
sahilmgandhi 18:6a4db94011d3 90
sahilmgandhi 18:6a4db94011d3 91 // set channel match to percentage
sahilmgandhi 18:6a4db94011d3 92 uint32_t v = (uint32_t)((float)(obj->pwm->MR0) * value);
sahilmgandhi 18:6a4db94011d3 93
sahilmgandhi 18:6a4db94011d3 94 // workaround for PWM1[1] - Never make it equal MR0, else we get 1 cycle dropout
sahilmgandhi 18:6a4db94011d3 95 if (v == obj->pwm->MR0) {
sahilmgandhi 18:6a4db94011d3 96 v++;
sahilmgandhi 18:6a4db94011d3 97 }
sahilmgandhi 18:6a4db94011d3 98
sahilmgandhi 18:6a4db94011d3 99 *obj->MR = v;
sahilmgandhi 18:6a4db94011d3 100
sahilmgandhi 18:6a4db94011d3 101 // accept on next period start
sahilmgandhi 18:6a4db94011d3 102 obj->pwm->LER |= 1 << obj->channel;
sahilmgandhi 18:6a4db94011d3 103 }
sahilmgandhi 18:6a4db94011d3 104
sahilmgandhi 18:6a4db94011d3 105 float pwmout_read(pwmout_t* obj) {
sahilmgandhi 18:6a4db94011d3 106 float v = (float)(*obj->MR) / (float)(obj->pwm->MR0);
sahilmgandhi 18:6a4db94011d3 107 return (v > 1.0f) ? (1.0f) : (v);
sahilmgandhi 18:6a4db94011d3 108 }
sahilmgandhi 18:6a4db94011d3 109
sahilmgandhi 18:6a4db94011d3 110 void pwmout_period(pwmout_t* obj, float seconds) {
sahilmgandhi 18:6a4db94011d3 111 pwmout_period_us(obj, seconds * 1000000.0f);
sahilmgandhi 18:6a4db94011d3 112 }
sahilmgandhi 18:6a4db94011d3 113
sahilmgandhi 18:6a4db94011d3 114 void pwmout_period_ms(pwmout_t* obj, int ms) {
sahilmgandhi 18:6a4db94011d3 115 pwmout_period_us(obj, ms * 1000);
sahilmgandhi 18:6a4db94011d3 116 }
sahilmgandhi 18:6a4db94011d3 117
sahilmgandhi 18:6a4db94011d3 118 // Set the PWM period, keeping the duty cycle the same.
sahilmgandhi 18:6a4db94011d3 119 void pwmout_period_us(pwmout_t* obj, int us) {
sahilmgandhi 18:6a4db94011d3 120 // calculate number of ticks
sahilmgandhi 18:6a4db94011d3 121 uint32_t ticks = pwm_clock_mhz * us;
sahilmgandhi 18:6a4db94011d3 122
sahilmgandhi 18:6a4db94011d3 123 // set reset
sahilmgandhi 18:6a4db94011d3 124 obj->pwm->TCR = TCR_RESET;
sahilmgandhi 18:6a4db94011d3 125
sahilmgandhi 18:6a4db94011d3 126 // set the global match register
sahilmgandhi 18:6a4db94011d3 127 obj->pwm->MR0 = ticks;
sahilmgandhi 18:6a4db94011d3 128
sahilmgandhi 18:6a4db94011d3 129 // Scale the pulse width to preserve the duty ratio
sahilmgandhi 18:6a4db94011d3 130 if (obj->pwm->MR0 > 0) {
sahilmgandhi 18:6a4db94011d3 131 *obj->MR = (*obj->MR * ticks) / obj->pwm->MR0;
sahilmgandhi 18:6a4db94011d3 132 }
sahilmgandhi 18:6a4db94011d3 133
sahilmgandhi 18:6a4db94011d3 134 // set the channel latch to update value at next period start
sahilmgandhi 18:6a4db94011d3 135 obj->pwm->LER |= 1 << 0;
sahilmgandhi 18:6a4db94011d3 136
sahilmgandhi 18:6a4db94011d3 137 // enable counter and pwm, clear reset
sahilmgandhi 18:6a4db94011d3 138 obj->pwm->TCR = TCR_CNT_EN | TCR_PWM_EN;
sahilmgandhi 18:6a4db94011d3 139 }
sahilmgandhi 18:6a4db94011d3 140
sahilmgandhi 18:6a4db94011d3 141 void pwmout_pulsewidth(pwmout_t* obj, float seconds) {
sahilmgandhi 18:6a4db94011d3 142 pwmout_pulsewidth_us(obj, seconds * 1000000.0f);
sahilmgandhi 18:6a4db94011d3 143 }
sahilmgandhi 18:6a4db94011d3 144
sahilmgandhi 18:6a4db94011d3 145 void pwmout_pulsewidth_ms(pwmout_t* obj, int ms) {
sahilmgandhi 18:6a4db94011d3 146 pwmout_pulsewidth_us(obj, ms * 1000);
sahilmgandhi 18:6a4db94011d3 147 }
sahilmgandhi 18:6a4db94011d3 148
sahilmgandhi 18:6a4db94011d3 149 void pwmout_pulsewidth_us(pwmout_t* obj, int us) {
sahilmgandhi 18:6a4db94011d3 150 // calculate number of ticks
sahilmgandhi 18:6a4db94011d3 151 uint32_t v = pwm_clock_mhz * us;
sahilmgandhi 18:6a4db94011d3 152
sahilmgandhi 18:6a4db94011d3 153 // workaround for PWM1[1] - Never make it equal MR0, else we get 1 cycle dropout
sahilmgandhi 18:6a4db94011d3 154 if (v == obj->pwm->MR0) {
sahilmgandhi 18:6a4db94011d3 155 v++;
sahilmgandhi 18:6a4db94011d3 156 }
sahilmgandhi 18:6a4db94011d3 157
sahilmgandhi 18:6a4db94011d3 158 // set the match register value
sahilmgandhi 18:6a4db94011d3 159 *obj->MR = v;
sahilmgandhi 18:6a4db94011d3 160
sahilmgandhi 18:6a4db94011d3 161 // set the channel latch to update value at next period start
sahilmgandhi 18:6a4db94011d3 162 obj->pwm->LER |= 1 << obj->channel;
sahilmgandhi 18:6a4db94011d3 163 }