MacroRat / MouseCode

Mouse code for the MacroRat

Dependencies:   ITG3200 QEI

mbed-dev/targets/TARGET_NXP/TARGET_LPC23XX/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_18, PWM_1, 2},
sahilmgandhi 18:6a4db94011d3 27 {P1_20, PWM_2, 2},
sahilmgandhi 18:6a4db94011d3 28 {P1_21, PWM_3, 2},
sahilmgandhi 18:6a4db94011d3 29 {P1_23, PWM_4, 2},
sahilmgandhi 18:6a4db94011d3 30 {P1_24, PWM_5, 2},
sahilmgandhi 18:6a4db94011d3 31 {P1_26, PWM_6, 2},
sahilmgandhi 18:6a4db94011d3 32 {P2_0 , PWM_1, 1},
sahilmgandhi 18:6a4db94011d3 33 {P2_1 , PWM_2, 1},
sahilmgandhi 18:6a4db94011d3 34 {P2_2 , PWM_3, 1},
sahilmgandhi 18:6a4db94011d3 35 {P2_3 , PWM_4, 1},
sahilmgandhi 18:6a4db94011d3 36 {P2_4 , PWM_5, 1},
sahilmgandhi 18:6a4db94011d3 37 {P2_5 , PWM_6, 1},
sahilmgandhi 18:6a4db94011d3 38 {P3_25, PWM_2, 3},
sahilmgandhi 18:6a4db94011d3 39 {P3_26, PWM_3, 3},
sahilmgandhi 18:6a4db94011d3 40 {NC, NC, 0}
sahilmgandhi 18:6a4db94011d3 41 };
sahilmgandhi 18:6a4db94011d3 42
sahilmgandhi 18:6a4db94011d3 43 __IO uint32_t *PWM_MATCH[] = {
sahilmgandhi 18:6a4db94011d3 44 &(LPC_PWM1->MR0),
sahilmgandhi 18:6a4db94011d3 45 &(LPC_PWM1->MR1),
sahilmgandhi 18:6a4db94011d3 46 &(LPC_PWM1->MR2),
sahilmgandhi 18:6a4db94011d3 47 &(LPC_PWM1->MR3),
sahilmgandhi 18:6a4db94011d3 48 &(LPC_PWM1->MR4),
sahilmgandhi 18:6a4db94011d3 49 &(LPC_PWM1->MR5),
sahilmgandhi 18:6a4db94011d3 50 &(LPC_PWM1->MR6)
sahilmgandhi 18:6a4db94011d3 51 };
sahilmgandhi 18:6a4db94011d3 52
sahilmgandhi 18:6a4db94011d3 53 #define TCR_PWM_EN 0x00000008
sahilmgandhi 18:6a4db94011d3 54
sahilmgandhi 18:6a4db94011d3 55 static unsigned int pwm_clock_mhz;
sahilmgandhi 18:6a4db94011d3 56
sahilmgandhi 18:6a4db94011d3 57 void pwmout_init(pwmout_t* obj, PinName pin) {
sahilmgandhi 18:6a4db94011d3 58 // determine the channel
sahilmgandhi 18:6a4db94011d3 59 PWMName pwm = (PWMName)pinmap_peripheral(pin, PinMap_PWM);
sahilmgandhi 18:6a4db94011d3 60 MBED_ASSERT(pwm != (PWMName)NC);
sahilmgandhi 18:6a4db94011d3 61
sahilmgandhi 18:6a4db94011d3 62 obj->pwm = pwm;
sahilmgandhi 18:6a4db94011d3 63 obj->MR = PWM_MATCH[pwm];
sahilmgandhi 18:6a4db94011d3 64
sahilmgandhi 18:6a4db94011d3 65 // ensure the power is on
sahilmgandhi 18:6a4db94011d3 66 LPC_SC->PCONP |= 1 << 6;
sahilmgandhi 18:6a4db94011d3 67
sahilmgandhi 18:6a4db94011d3 68 // ensure clock to /4
sahilmgandhi 18:6a4db94011d3 69 LPC_SC->PCLKSEL0 &= ~(0x3 << 12); // pclk = /4
sahilmgandhi 18:6a4db94011d3 70 LPC_PWM1->PR = 0; // no pre-scale
sahilmgandhi 18:6a4db94011d3 71
sahilmgandhi 18:6a4db94011d3 72 // ensure single PWM mode
sahilmgandhi 18:6a4db94011d3 73 LPC_PWM1->MCR = 1 << 1; // reset TC on match 0
sahilmgandhi 18:6a4db94011d3 74
sahilmgandhi 18:6a4db94011d3 75 // enable the specific PWM output
sahilmgandhi 18:6a4db94011d3 76 LPC_PWM1->PCR |= 1 << (8 + pwm);
sahilmgandhi 18:6a4db94011d3 77
sahilmgandhi 18:6a4db94011d3 78 pwm_clock_mhz = SystemCoreClock / 4000000;
sahilmgandhi 18:6a4db94011d3 79
sahilmgandhi 18:6a4db94011d3 80 // default to 20ms: standard for servos, and fine for e.g. brightness control
sahilmgandhi 18:6a4db94011d3 81 pwmout_period_ms(obj, 20);
sahilmgandhi 18:6a4db94011d3 82 pwmout_write (obj, 0);
sahilmgandhi 18:6a4db94011d3 83
sahilmgandhi 18:6a4db94011d3 84 // Wire pinout
sahilmgandhi 18:6a4db94011d3 85 pinmap_pinout(pin, PinMap_PWM);
sahilmgandhi 18:6a4db94011d3 86 }
sahilmgandhi 18:6a4db94011d3 87
sahilmgandhi 18:6a4db94011d3 88 void pwmout_free(pwmout_t* obj) {
sahilmgandhi 18:6a4db94011d3 89 // [TODO]
sahilmgandhi 18:6a4db94011d3 90 }
sahilmgandhi 18:6a4db94011d3 91
sahilmgandhi 18:6a4db94011d3 92 void pwmout_write(pwmout_t* obj, float value) {
sahilmgandhi 18:6a4db94011d3 93 if (value < 0.0f) {
sahilmgandhi 18:6a4db94011d3 94 value = 0.0;
sahilmgandhi 18:6a4db94011d3 95 } else if (value > 1.0f) {
sahilmgandhi 18:6a4db94011d3 96 value = 1.0;
sahilmgandhi 18:6a4db94011d3 97 }
sahilmgandhi 18:6a4db94011d3 98
sahilmgandhi 18:6a4db94011d3 99 // set channel match to percentage
sahilmgandhi 18:6a4db94011d3 100 uint32_t v = (uint32_t)((float)(LPC_PWM1->MR0) * value);
sahilmgandhi 18:6a4db94011d3 101
sahilmgandhi 18:6a4db94011d3 102 // workaround for PWM1[1] - Never make it equal MR0, else we get 1 cycle dropout
sahilmgandhi 18:6a4db94011d3 103 if (v == LPC_PWM1->MR0) {
sahilmgandhi 18:6a4db94011d3 104 v++;
sahilmgandhi 18:6a4db94011d3 105 }
sahilmgandhi 18:6a4db94011d3 106
sahilmgandhi 18:6a4db94011d3 107 *obj->MR = v;
sahilmgandhi 18:6a4db94011d3 108
sahilmgandhi 18:6a4db94011d3 109 // accept on next period start
sahilmgandhi 18:6a4db94011d3 110 LPC_PWM1->LER |= 1 << obj->pwm;
sahilmgandhi 18:6a4db94011d3 111 }
sahilmgandhi 18:6a4db94011d3 112
sahilmgandhi 18:6a4db94011d3 113 float pwmout_read(pwmout_t* obj) {
sahilmgandhi 18:6a4db94011d3 114 float v = (float)(*obj->MR) / (float)(LPC_PWM1->MR0);
sahilmgandhi 18:6a4db94011d3 115 return (v > 1.0f) ? (1.0f) : (v);
sahilmgandhi 18:6a4db94011d3 116 }
sahilmgandhi 18:6a4db94011d3 117
sahilmgandhi 18:6a4db94011d3 118 void pwmout_period(pwmout_t* obj, float seconds) {
sahilmgandhi 18:6a4db94011d3 119 pwmout_period_us(obj, seconds * 1000000.0f);
sahilmgandhi 18:6a4db94011d3 120 }
sahilmgandhi 18:6a4db94011d3 121
sahilmgandhi 18:6a4db94011d3 122 void pwmout_period_ms(pwmout_t* obj, int ms) {
sahilmgandhi 18:6a4db94011d3 123 pwmout_period_us(obj, ms * 1000);
sahilmgandhi 18:6a4db94011d3 124 }
sahilmgandhi 18:6a4db94011d3 125
sahilmgandhi 18:6a4db94011d3 126 // Set the PWM period, keeping the duty cycle the same.
sahilmgandhi 18:6a4db94011d3 127 void pwmout_period_us(pwmout_t* obj, int us) {
sahilmgandhi 18:6a4db94011d3 128 // calculate number of ticks
sahilmgandhi 18:6a4db94011d3 129 uint32_t ticks = pwm_clock_mhz * us;
sahilmgandhi 18:6a4db94011d3 130
sahilmgandhi 18:6a4db94011d3 131 // set reset
sahilmgandhi 18:6a4db94011d3 132 LPC_PWM1->TCR = TCR_RESET;
sahilmgandhi 18:6a4db94011d3 133
sahilmgandhi 18:6a4db94011d3 134 // set the global match register
sahilmgandhi 18:6a4db94011d3 135 LPC_PWM1->MR0 = ticks;
sahilmgandhi 18:6a4db94011d3 136
sahilmgandhi 18:6a4db94011d3 137 // Scale the pulse width to preserve the duty ratio
sahilmgandhi 18:6a4db94011d3 138 if (LPC_PWM1->MR0 > 0) {
sahilmgandhi 18:6a4db94011d3 139 *obj->MR = (*obj->MR * ticks) / LPC_PWM1->MR0;
sahilmgandhi 18:6a4db94011d3 140 }
sahilmgandhi 18:6a4db94011d3 141
sahilmgandhi 18:6a4db94011d3 142 // set the channel latch to update value at next period start
sahilmgandhi 18:6a4db94011d3 143 LPC_PWM1->LER |= 1 << 0;
sahilmgandhi 18:6a4db94011d3 144
sahilmgandhi 18:6a4db94011d3 145 // enable counter and pwm, clear reset
sahilmgandhi 18:6a4db94011d3 146 LPC_PWM1->TCR = TCR_CNT_EN | TCR_PWM_EN;
sahilmgandhi 18:6a4db94011d3 147 }
sahilmgandhi 18:6a4db94011d3 148
sahilmgandhi 18:6a4db94011d3 149 void pwmout_pulsewidth(pwmout_t* obj, float seconds) {
sahilmgandhi 18:6a4db94011d3 150 pwmout_pulsewidth_us(obj, seconds * 1000000.0f);
sahilmgandhi 18:6a4db94011d3 151 }
sahilmgandhi 18:6a4db94011d3 152
sahilmgandhi 18:6a4db94011d3 153 void pwmout_pulsewidth_ms(pwmout_t* obj, int ms) {
sahilmgandhi 18:6a4db94011d3 154 pwmout_pulsewidth_us(obj, ms * 1000);
sahilmgandhi 18:6a4db94011d3 155 }
sahilmgandhi 18:6a4db94011d3 156
sahilmgandhi 18:6a4db94011d3 157 void pwmout_pulsewidth_us(pwmout_t* obj, int us) {
sahilmgandhi 18:6a4db94011d3 158 // calculate number of ticks
sahilmgandhi 18:6a4db94011d3 159 uint32_t v = pwm_clock_mhz * us;
sahilmgandhi 18:6a4db94011d3 160
sahilmgandhi 18:6a4db94011d3 161 // workaround for PWM1[1] - Never make it equal MR0, else we get 1 cycle dropout
sahilmgandhi 18:6a4db94011d3 162 if (v == LPC_PWM1->MR0) {
sahilmgandhi 18:6a4db94011d3 163 v++;
sahilmgandhi 18:6a4db94011d3 164 }
sahilmgandhi 18:6a4db94011d3 165
sahilmgandhi 18:6a4db94011d3 166 // set the match register value
sahilmgandhi 18:6a4db94011d3 167 *obj->MR = v;
sahilmgandhi 18:6a4db94011d3 168
sahilmgandhi 18:6a4db94011d3 169 // set the channel latch to update value at next period start
sahilmgandhi 18:6a4db94011d3 170 LPC_PWM1->LER |= 1 << obj->pwm;
sahilmgandhi 18:6a4db94011d3 171 }