MacroRat / MouseCode

Mouse code for the MacroRat

Dependencies:   ITG3200 QEI

mbed-dev/targets/TARGET_NXP/TARGET_LPC11XX_11CXX/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 /* To have a PWM where we can change both the period and the duty cycle,
sahilmgandhi 18:6a4db94011d3 25 * we need an entire timer. With the following conventions:
sahilmgandhi 18:6a4db94011d3 26 * * MR3 is used for the PWM period
sahilmgandhi 18:6a4db94011d3 27 * * MR0, MR1, MR2 are used for the duty cycle
sahilmgandhi 18:6a4db94011d3 28 */
sahilmgandhi 18:6a4db94011d3 29 static const PinMap PinMap_PWM[] = {
sahilmgandhi 18:6a4db94011d3 30 /* CT16B0 */
sahilmgandhi 18:6a4db94011d3 31 {P0_8 , PWM_1, 0x02}, /* MR0 */
sahilmgandhi 18:6a4db94011d3 32 {P0_9 , PWM_2, 0x02}, /* MR1 */
sahilmgandhi 18:6a4db94011d3 33
sahilmgandhi 18:6a4db94011d3 34 /* CT16B1 */
sahilmgandhi 18:6a4db94011d3 35 {P1_9 , PWM_3, 0x01}, /* MR0 */
sahilmgandhi 18:6a4db94011d3 36 {P1_10, PWM_4, 0x02}, /* MR1 */
sahilmgandhi 18:6a4db94011d3 37
sahilmgandhi 18:6a4db94011d3 38 /* CT32B0 */
sahilmgandhi 18:6a4db94011d3 39 {P0_1 , PWM_5, 0x02}, /* MR2 */
sahilmgandhi 18:6a4db94011d3 40
sahilmgandhi 18:6a4db94011d3 41 {NC , NC ,0x00}
sahilmgandhi 18:6a4db94011d3 42 };
sahilmgandhi 18:6a4db94011d3 43
sahilmgandhi 18:6a4db94011d3 44 typedef struct {
sahilmgandhi 18:6a4db94011d3 45 uint8_t timer;
sahilmgandhi 18:6a4db94011d3 46 uint8_t mr;
sahilmgandhi 18:6a4db94011d3 47 } timer_mr;
sahilmgandhi 18:6a4db94011d3 48
sahilmgandhi 18:6a4db94011d3 49 static timer_mr pwm_timer_map[5] = {
sahilmgandhi 18:6a4db94011d3 50 {0, 0}, /* CT16B0, MR0 */
sahilmgandhi 18:6a4db94011d3 51 {0, 1}, /* CT16B0, MR1 */
sahilmgandhi 18:6a4db94011d3 52
sahilmgandhi 18:6a4db94011d3 53 {1, 0}, /* CT16B1, MR0 */
sahilmgandhi 18:6a4db94011d3 54 {1, 1}, /* CT16B1, MR1 */
sahilmgandhi 18:6a4db94011d3 55
sahilmgandhi 18:6a4db94011d3 56 {2, 2}, /* CT32B0, MR2 */
sahilmgandhi 18:6a4db94011d3 57 };
sahilmgandhi 18:6a4db94011d3 58
sahilmgandhi 18:6a4db94011d3 59 static LPC_TMR_TypeDef *Timers[3] = {
sahilmgandhi 18:6a4db94011d3 60 LPC_TMR16B0, LPC_TMR16B1,
sahilmgandhi 18:6a4db94011d3 61 LPC_TMR32B0
sahilmgandhi 18:6a4db94011d3 62 };
sahilmgandhi 18:6a4db94011d3 63
sahilmgandhi 18:6a4db94011d3 64 void pwmout_init(pwmout_t* obj, PinName pin) {
sahilmgandhi 18:6a4db94011d3 65 // determine the channel
sahilmgandhi 18:6a4db94011d3 66 PWMName pwm = (PWMName)pinmap_peripheral(pin, PinMap_PWM);
sahilmgandhi 18:6a4db94011d3 67 MBED_ASSERT(pwm != (PWMName)NC);
sahilmgandhi 18:6a4db94011d3 68
sahilmgandhi 18:6a4db94011d3 69 obj->pwm = pwm;
sahilmgandhi 18:6a4db94011d3 70
sahilmgandhi 18:6a4db94011d3 71 // Timer registers
sahilmgandhi 18:6a4db94011d3 72 timer_mr tid = pwm_timer_map[pwm];
sahilmgandhi 18:6a4db94011d3 73 LPC_TMR_TypeDef *timer = Timers[tid.timer];
sahilmgandhi 18:6a4db94011d3 74
sahilmgandhi 18:6a4db94011d3 75 // Disable timer
sahilmgandhi 18:6a4db94011d3 76 timer->TCR = 0;
sahilmgandhi 18:6a4db94011d3 77
sahilmgandhi 18:6a4db94011d3 78 // Power the correspondent timer
sahilmgandhi 18:6a4db94011d3 79 LPC_SYSCON->SYSAHBCLKCTRL |= 1 << (tid.timer + 7);
sahilmgandhi 18:6a4db94011d3 80
sahilmgandhi 18:6a4db94011d3 81 /* Enable PWM function */
sahilmgandhi 18:6a4db94011d3 82 timer->PWMC = (1 << 3)|(1 << 2)|(1 << 1)|(1 << 0);
sahilmgandhi 18:6a4db94011d3 83
sahilmgandhi 18:6a4db94011d3 84 /* Reset Functionality on MR3 controlling the PWM period */
sahilmgandhi 18:6a4db94011d3 85 timer->MCR = 1 << 10;
sahilmgandhi 18:6a4db94011d3 86
sahilmgandhi 18:6a4db94011d3 87 if (timer == LPC_TMR16B0 || timer == LPC_TMR16B1) {
sahilmgandhi 18:6a4db94011d3 88 /* Set 16-bit timer prescaler to avoid timer expire for default 20ms */
sahilmgandhi 18:6a4db94011d3 89 /* This can be also modified by user application, but the prescaler value */
sahilmgandhi 18:6a4db94011d3 90 /* might be trade-off to timer accuracy */
sahilmgandhi 18:6a4db94011d3 91 timer->PR = 30;
sahilmgandhi 18:6a4db94011d3 92 }
sahilmgandhi 18:6a4db94011d3 93
sahilmgandhi 18:6a4db94011d3 94 // default to 20ms: standard for servos, and fine for e.g. brightness control
sahilmgandhi 18:6a4db94011d3 95 pwmout_period_ms(obj, 20);
sahilmgandhi 18:6a4db94011d3 96 pwmout_write (obj, 0);
sahilmgandhi 18:6a4db94011d3 97
sahilmgandhi 18:6a4db94011d3 98 // Wire pinout
sahilmgandhi 18:6a4db94011d3 99 pinmap_pinout(pin, PinMap_PWM);
sahilmgandhi 18:6a4db94011d3 100 }
sahilmgandhi 18:6a4db94011d3 101
sahilmgandhi 18:6a4db94011d3 102 void pwmout_free(pwmout_t* obj) {
sahilmgandhi 18:6a4db94011d3 103 // [TODO]
sahilmgandhi 18:6a4db94011d3 104 }
sahilmgandhi 18:6a4db94011d3 105
sahilmgandhi 18:6a4db94011d3 106 void pwmout_write(pwmout_t* obj, float value) {
sahilmgandhi 18:6a4db94011d3 107 if (value < 0.0f) {
sahilmgandhi 18:6a4db94011d3 108 value = 0.0;
sahilmgandhi 18:6a4db94011d3 109 } else if (value > 1.0f) {
sahilmgandhi 18:6a4db94011d3 110 value = 1.0;
sahilmgandhi 18:6a4db94011d3 111 }
sahilmgandhi 18:6a4db94011d3 112
sahilmgandhi 18:6a4db94011d3 113 timer_mr tid = pwm_timer_map[obj->pwm];
sahilmgandhi 18:6a4db94011d3 114 LPC_TMR_TypeDef *timer = Timers[tid.timer];
sahilmgandhi 18:6a4db94011d3 115 uint32_t t_off = timer->MR3 - (uint32_t)((float)(timer->MR3) * value);
sahilmgandhi 18:6a4db94011d3 116 // to avoid spike pulse when duty is 0%
sahilmgandhi 18:6a4db94011d3 117 if (value == 0) {
sahilmgandhi 18:6a4db94011d3 118 t_off++;
sahilmgandhi 18:6a4db94011d3 119 }
sahilmgandhi 18:6a4db94011d3 120
sahilmgandhi 18:6a4db94011d3 121 timer->TCR = TCR_RESET;
sahilmgandhi 18:6a4db94011d3 122 timer->MR[tid.mr] = t_off;
sahilmgandhi 18:6a4db94011d3 123 timer->TCR = TCR_CNT_EN;
sahilmgandhi 18:6a4db94011d3 124 }
sahilmgandhi 18:6a4db94011d3 125
sahilmgandhi 18:6a4db94011d3 126 float pwmout_read(pwmout_t* obj) {
sahilmgandhi 18:6a4db94011d3 127 timer_mr tid = pwm_timer_map[obj->pwm];
sahilmgandhi 18:6a4db94011d3 128 LPC_TMR_TypeDef *timer = Timers[tid.timer];
sahilmgandhi 18:6a4db94011d3 129
sahilmgandhi 18:6a4db94011d3 130 float v = (float)(timer->MR3 - timer->MR[tid.mr]) / (float)(timer->MR3);
sahilmgandhi 18:6a4db94011d3 131 if (timer->MR[tid.mr] > timer->MR3) {
sahilmgandhi 18:6a4db94011d3 132 v = 0.0f;
sahilmgandhi 18:6a4db94011d3 133 }
sahilmgandhi 18:6a4db94011d3 134 return (v > 1.0f) ? (1.0f) : (v);
sahilmgandhi 18:6a4db94011d3 135 }
sahilmgandhi 18:6a4db94011d3 136
sahilmgandhi 18:6a4db94011d3 137 void pwmout_period(pwmout_t* obj, float seconds) {
sahilmgandhi 18:6a4db94011d3 138 pwmout_period_us(obj, seconds * 1000000.0f);
sahilmgandhi 18:6a4db94011d3 139 }
sahilmgandhi 18:6a4db94011d3 140
sahilmgandhi 18:6a4db94011d3 141 void pwmout_period_ms(pwmout_t* obj, int ms) {
sahilmgandhi 18:6a4db94011d3 142 pwmout_period_us(obj, ms * 1000);
sahilmgandhi 18:6a4db94011d3 143 }
sahilmgandhi 18:6a4db94011d3 144
sahilmgandhi 18:6a4db94011d3 145 // Set the PWM period, keeping the duty cycle the same.
sahilmgandhi 18:6a4db94011d3 146 void pwmout_period_us(pwmout_t* obj, int us) {
sahilmgandhi 18:6a4db94011d3 147 int i = 0;
sahilmgandhi 18:6a4db94011d3 148 uint32_t period_ticks;
sahilmgandhi 18:6a4db94011d3 149
sahilmgandhi 18:6a4db94011d3 150 timer_mr tid = pwm_timer_map[obj->pwm];
sahilmgandhi 18:6a4db94011d3 151 LPC_TMR_TypeDef *timer = Timers[tid.timer];
sahilmgandhi 18:6a4db94011d3 152 uint32_t old_period_ticks = timer->MR3;
sahilmgandhi 18:6a4db94011d3 153 period_ticks = (SystemCoreClock / 1000000 * us) / (timer->PR + 1);
sahilmgandhi 18:6a4db94011d3 154
sahilmgandhi 18:6a4db94011d3 155 timer->TCR = TCR_RESET;
sahilmgandhi 18:6a4db94011d3 156 timer->MR3 = period_ticks;
sahilmgandhi 18:6a4db94011d3 157
sahilmgandhi 18:6a4db94011d3 158 // Scale the pulse width to preserve the duty ratio
sahilmgandhi 18:6a4db94011d3 159 if (old_period_ticks > 0) {
sahilmgandhi 18:6a4db94011d3 160 for (i=0; i<3; i++) {
sahilmgandhi 18:6a4db94011d3 161 uint32_t t_off = period_ticks - (uint32_t)(((uint64_t)timer->MR[i] * (uint64_t)period_ticks) / (uint64_t)old_period_ticks);
sahilmgandhi 18:6a4db94011d3 162 timer->MR[i] = t_off;
sahilmgandhi 18:6a4db94011d3 163 }
sahilmgandhi 18:6a4db94011d3 164 }
sahilmgandhi 18:6a4db94011d3 165 timer->TCR = TCR_CNT_EN;
sahilmgandhi 18:6a4db94011d3 166 }
sahilmgandhi 18:6a4db94011d3 167
sahilmgandhi 18:6a4db94011d3 168 void pwmout_pulsewidth(pwmout_t* obj, float seconds) {
sahilmgandhi 18:6a4db94011d3 169 pwmout_pulsewidth_us(obj, seconds * 1000000.0f);
sahilmgandhi 18:6a4db94011d3 170 }
sahilmgandhi 18:6a4db94011d3 171
sahilmgandhi 18:6a4db94011d3 172 void pwmout_pulsewidth_ms(pwmout_t* obj, int ms) {
sahilmgandhi 18:6a4db94011d3 173 pwmout_pulsewidth_us(obj, ms * 1000);
sahilmgandhi 18:6a4db94011d3 174 }
sahilmgandhi 18:6a4db94011d3 175
sahilmgandhi 18:6a4db94011d3 176 void pwmout_pulsewidth_us(pwmout_t* obj, int us) {
sahilmgandhi 18:6a4db94011d3 177 timer_mr tid = pwm_timer_map[obj->pwm];
sahilmgandhi 18:6a4db94011d3 178 LPC_TMR_TypeDef *timer = Timers[tid.timer];
sahilmgandhi 18:6a4db94011d3 179 uint32_t t_on = (uint32_t)((((uint64_t)SystemCoreClock * (uint64_t)us) / (uint64_t)1000000) / (timer->PR + 1));
sahilmgandhi 18:6a4db94011d3 180
sahilmgandhi 18:6a4db94011d3 181 timer->TCR = TCR_RESET;
sahilmgandhi 18:6a4db94011d3 182 if (t_on > timer->MR3) {
sahilmgandhi 18:6a4db94011d3 183 pwmout_period_us(obj, us);
sahilmgandhi 18:6a4db94011d3 184 }
sahilmgandhi 18:6a4db94011d3 185 uint32_t t_off = timer->MR3 - t_on;
sahilmgandhi 18:6a4db94011d3 186 timer->MR[tid.mr] = t_off;
sahilmgandhi 18:6a4db94011d3 187 timer->TCR = TCR_CNT_EN;
sahilmgandhi 18:6a4db94011d3 188 }