mbed library sources
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targets/hal/TARGET_NXP/TARGET_LPC82X/pwmout_api.c@613:bc40b8d2aec4, 2015-08-20 (annotated)
- Committer:
- mbed_official
- Date:
- Thu Aug 20 10:45:13 2015 +0100
- Revision:
- 613:bc40b8d2aec4
- Parent:
- 557:42efda18ac92
Synchronized with git revision 92ca8c7b60a283b6bb60eb65b183dac1599f0ade
Full URL: https://github.com/mbedmicro/mbed/commit/92ca8c7b60a283b6bb60eb65b183dac1599f0ade/
Nordic: update application start address in GCC linker script
Who changed what in which revision?
User | Revision | Line number | New contents of line |
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mbed_official | 337:6ed01c00b962 | 1 | /* mbed Microcontroller Library |
mbed_official | 337:6ed01c00b962 | 2 | * Copyright (c) 2006-2013 ARM Limited |
mbed_official | 337:6ed01c00b962 | 3 | * |
mbed_official | 337:6ed01c00b962 | 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
mbed_official | 337:6ed01c00b962 | 5 | * you may not use this file except in compliance with the License. |
mbed_official | 337:6ed01c00b962 | 6 | * You may obtain a copy of the License at |
mbed_official | 337:6ed01c00b962 | 7 | * |
mbed_official | 337:6ed01c00b962 | 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
mbed_official | 337:6ed01c00b962 | 9 | * |
mbed_official | 337:6ed01c00b962 | 10 | * Unless required by applicable law or agreed to in writing, software |
mbed_official | 337:6ed01c00b962 | 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
mbed_official | 337:6ed01c00b962 | 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
mbed_official | 337:6ed01c00b962 | 13 | * See the License for the specific language governing permissions and |
mbed_official | 337:6ed01c00b962 | 14 | * limitations under the License. |
mbed_official | 337:6ed01c00b962 | 15 | */ |
mbed_official | 337:6ed01c00b962 | 16 | #include "mbed_assert.h" |
mbed_official | 337:6ed01c00b962 | 17 | #include "pwmout_api.h" |
mbed_official | 337:6ed01c00b962 | 18 | #include "cmsis.h" |
mbed_official | 337:6ed01c00b962 | 19 | #include "pinmap.h" |
mbed_official | 337:6ed01c00b962 | 20 | #include "mbed_error.h" |
mbed_official | 337:6ed01c00b962 | 21 | |
mbed_official | 337:6ed01c00b962 | 22 | #if DEVICE_PWMOUT |
mbed_official | 337:6ed01c00b962 | 23 | |
mbed_official | 337:6ed01c00b962 | 24 | // bit flags for used SCTs |
mbed_official | 337:6ed01c00b962 | 25 | static unsigned char sct_used = 0; |
mbed_official | 337:6ed01c00b962 | 26 | |
mbed_official | 337:6ed01c00b962 | 27 | static int get_available_sct() |
mbed_official | 337:6ed01c00b962 | 28 | { |
mbed_official | 337:6ed01c00b962 | 29 | int i; |
mbed_official | 337:6ed01c00b962 | 30 | for (i = 0; i < 4; i++) { |
mbed_official | 337:6ed01c00b962 | 31 | if ((sct_used & (1 << i)) == 0) |
mbed_official | 337:6ed01c00b962 | 32 | return i; |
mbed_official | 337:6ed01c00b962 | 33 | } |
mbed_official | 337:6ed01c00b962 | 34 | return -1; |
mbed_official | 337:6ed01c00b962 | 35 | } |
mbed_official | 337:6ed01c00b962 | 36 | |
mbed_official | 337:6ed01c00b962 | 37 | void pwmout_init(pwmout_t* obj, PinName pin) |
mbed_official | 337:6ed01c00b962 | 38 | { |
mbed_official | 557:42efda18ac92 | 39 | MBED_ASSERT(pin != (PinName)NC); |
mbed_official | 337:6ed01c00b962 | 40 | |
mbed_official | 337:6ed01c00b962 | 41 | int sct_n = get_available_sct(); |
mbed_official | 337:6ed01c00b962 | 42 | if (sct_n == -1) { |
mbed_official | 337:6ed01c00b962 | 43 | error("No available SCT"); |
mbed_official | 337:6ed01c00b962 | 44 | } |
mbed_official | 337:6ed01c00b962 | 45 | |
mbed_official | 337:6ed01c00b962 | 46 | sct_used |= (1 << sct_n); |
mbed_official | 337:6ed01c00b962 | 47 | |
mbed_official | 337:6ed01c00b962 | 48 | obj->pwm = (LPC_SCT_Type*)LPC_SCT; |
mbed_official | 337:6ed01c00b962 | 49 | obj->pwm_ch = sct_n; |
mbed_official | 337:6ed01c00b962 | 50 | |
mbed_official | 516:b3fb5c6901a6 | 51 | LPC_SCT_Type* pwm = obj->pwm; |
mbed_official | 337:6ed01c00b962 | 52 | |
mbed_official | 337:6ed01c00b962 | 53 | // Enable the SCT clock |
mbed_official | 337:6ed01c00b962 | 54 | LPC_SYSCON->SYSAHBCLKCTRL |= (1 << 8); |
mbed_official | 337:6ed01c00b962 | 55 | |
mbed_official | 337:6ed01c00b962 | 56 | // Clear peripheral reset the SCT: |
mbed_official | 337:6ed01c00b962 | 57 | LPC_SYSCON->PRESETCTRL |= (1 << 8); |
mbed_official | 337:6ed01c00b962 | 58 | |
mbed_official | 337:6ed01c00b962 | 59 | switch(sct_n) { |
mbed_official | 337:6ed01c00b962 | 60 | case 0: |
mbed_official | 337:6ed01c00b962 | 61 | // SCT_OUT0 |
mbed_official | 337:6ed01c00b962 | 62 | LPC_SWM->PINASSIGN[7] &= ~0xFF000000; |
mbed_official | 337:6ed01c00b962 | 63 | LPC_SWM->PINASSIGN[7] |= ((pin >> PIN_SHIFT) << 24); |
mbed_official | 337:6ed01c00b962 | 64 | break; |
mbed_official | 337:6ed01c00b962 | 65 | case 1: |
mbed_official | 337:6ed01c00b962 | 66 | // SCT_OUT1 |
mbed_official | 337:6ed01c00b962 | 67 | LPC_SWM->PINASSIGN[8] &= ~0x000000FF; |
mbed_official | 337:6ed01c00b962 | 68 | LPC_SWM->PINASSIGN[8] |= (pin >> PIN_SHIFT); |
mbed_official | 337:6ed01c00b962 | 69 | break; |
mbed_official | 337:6ed01c00b962 | 70 | case 2: |
mbed_official | 337:6ed01c00b962 | 71 | // SCT2_OUT2 |
mbed_official | 337:6ed01c00b962 | 72 | LPC_SWM->PINASSIGN[8] &= ~0x0000FF00; |
mbed_official | 337:6ed01c00b962 | 73 | LPC_SWM->PINASSIGN[8] |= ((pin >> PIN_SHIFT) << 8); |
mbed_official | 337:6ed01c00b962 | 74 | break; |
mbed_official | 337:6ed01c00b962 | 75 | case 3: |
mbed_official | 337:6ed01c00b962 | 76 | // SCT3_OUT3 |
mbed_official | 337:6ed01c00b962 | 77 | LPC_SWM->PINASSIGN[8] &= ~0x00FF0000; |
mbed_official | 337:6ed01c00b962 | 78 | LPC_SWM->PINASSIGN[8] |= ((pin >> PIN_SHIFT) << 16); |
mbed_official | 337:6ed01c00b962 | 79 | break; |
mbed_official | 337:6ed01c00b962 | 80 | default: |
mbed_official | 337:6ed01c00b962 | 81 | break; |
mbed_official | 337:6ed01c00b962 | 82 | } |
mbed_official | 337:6ed01c00b962 | 83 | |
mbed_official | 516:b3fb5c6901a6 | 84 | // Unified 32-bit counter, autolimit |
mbed_official | 516:b3fb5c6901a6 | 85 | pwm->CONFIG |= ((0x3 << 17) | 0x01); |
mbed_official | 337:6ed01c00b962 | 86 | |
mbed_official | 337:6ed01c00b962 | 87 | // halt and clear the counter |
mbed_official | 337:6ed01c00b962 | 88 | pwm->CTRL |= (1 << 2) | (1 << 3); |
mbed_official | 337:6ed01c00b962 | 89 | |
mbed_official | 337:6ed01c00b962 | 90 | // System Clock -> us_ticker (1)MHz |
mbed_official | 337:6ed01c00b962 | 91 | pwm->CTRL &= ~(0x7F << 5); |
mbed_official | 337:6ed01c00b962 | 92 | pwm->CTRL |= (((SystemCoreClock/1000000 - 1) & 0x7F) << 5); |
mbed_official | 337:6ed01c00b962 | 93 | |
mbed_official | 337:6ed01c00b962 | 94 | pwm->OUT[sct_n].SET = (1 << ((sct_n * 2) + 0)); |
mbed_official | 337:6ed01c00b962 | 95 | pwm->OUT[sct_n].CLR = (1 << ((sct_n * 2) + 1)); |
mbed_official | 337:6ed01c00b962 | 96 | |
mbed_official | 337:6ed01c00b962 | 97 | pwm->EVENT[(sct_n * 2) + 0].CTRL = (1 << 12) | ((sct_n * 2) + 0); // match event |
mbed_official | 337:6ed01c00b962 | 98 | pwm->EVENT[(sct_n * 2) + 0].STATE = 0xFFFFFFFF; |
mbed_official | 337:6ed01c00b962 | 99 | pwm->EVENT[(sct_n * 2) + 1].CTRL = (1 << 12) | ((sct_n * 2) + 1); |
mbed_official | 337:6ed01c00b962 | 100 | pwm->EVENT[(sct_n * 2) + 1].STATE = 0xFFFFFFFF; |
mbed_official | 337:6ed01c00b962 | 101 | |
mbed_official | 337:6ed01c00b962 | 102 | // unhalt the counter: |
mbed_official | 337:6ed01c00b962 | 103 | // - clearing bit 2 of the CTRL register |
mbed_official | 337:6ed01c00b962 | 104 | pwm->CTRL &= ~(1 << 2); |
mbed_official | 337:6ed01c00b962 | 105 | |
mbed_official | 337:6ed01c00b962 | 106 | // default to 20ms: standard for servos, and fine for e.g. brightness control |
mbed_official | 337:6ed01c00b962 | 107 | pwmout_period_ms(obj, 20); |
mbed_official | 337:6ed01c00b962 | 108 | pwmout_write (obj, 0); |
mbed_official | 337:6ed01c00b962 | 109 | } |
mbed_official | 337:6ed01c00b962 | 110 | |
mbed_official | 337:6ed01c00b962 | 111 | void pwmout_free(pwmout_t* obj) |
mbed_official | 337:6ed01c00b962 | 112 | { |
mbed_official | 337:6ed01c00b962 | 113 | // Disable the SCT clock |
mbed_official | 337:6ed01c00b962 | 114 | LPC_SYSCON->SYSAHBCLKCTRL &= ~(1 << 8); |
mbed_official | 337:6ed01c00b962 | 115 | sct_used &= ~(1 << obj->pwm_ch); |
mbed_official | 337:6ed01c00b962 | 116 | } |
mbed_official | 337:6ed01c00b962 | 117 | |
mbed_official | 337:6ed01c00b962 | 118 | void pwmout_write(pwmout_t* obj, float value) |
mbed_official | 337:6ed01c00b962 | 119 | { |
mbed_official | 337:6ed01c00b962 | 120 | if (value < 0.0f) { |
mbed_official | 337:6ed01c00b962 | 121 | value = 0.0; |
mbed_official | 337:6ed01c00b962 | 122 | } else if (value > 1.0f) { |
mbed_official | 337:6ed01c00b962 | 123 | value = 1.0; |
mbed_official | 337:6ed01c00b962 | 124 | } |
mbed_official | 337:6ed01c00b962 | 125 | uint32_t t_on = (uint32_t)((float)(obj->pwm->MATCHREL[obj->pwm_ch * 2]) * value); |
mbed_official | 337:6ed01c00b962 | 126 | obj->pwm->MATCHREL[(obj->pwm_ch * 2) + 1] = t_on; |
mbed_official | 337:6ed01c00b962 | 127 | } |
mbed_official | 337:6ed01c00b962 | 128 | |
mbed_official | 337:6ed01c00b962 | 129 | float pwmout_read(pwmout_t* obj) |
mbed_official | 337:6ed01c00b962 | 130 | { |
mbed_official | 337:6ed01c00b962 | 131 | uint32_t t_off = obj->pwm->MATCHREL[(obj->pwm_ch * 2) + 0]; |
mbed_official | 337:6ed01c00b962 | 132 | uint32_t t_on = obj->pwm->MATCHREL[(obj->pwm_ch * 2) + 1]; |
mbed_official | 337:6ed01c00b962 | 133 | float v = (float)t_on/(float)t_off; |
mbed_official | 337:6ed01c00b962 | 134 | return (v > 1.0f) ? (1.0f) : (v); |
mbed_official | 337:6ed01c00b962 | 135 | } |
mbed_official | 337:6ed01c00b962 | 136 | |
mbed_official | 337:6ed01c00b962 | 137 | void pwmout_period(pwmout_t* obj, float seconds) |
mbed_official | 337:6ed01c00b962 | 138 | { |
mbed_official | 337:6ed01c00b962 | 139 | pwmout_period_us(obj, seconds * 1000000.0f); |
mbed_official | 337:6ed01c00b962 | 140 | } |
mbed_official | 337:6ed01c00b962 | 141 | |
mbed_official | 337:6ed01c00b962 | 142 | void pwmout_period_ms(pwmout_t* obj, int ms) |
mbed_official | 337:6ed01c00b962 | 143 | { |
mbed_official | 337:6ed01c00b962 | 144 | pwmout_period_us(obj, ms * 1000); |
mbed_official | 337:6ed01c00b962 | 145 | } |
mbed_official | 337:6ed01c00b962 | 146 | |
mbed_official | 337:6ed01c00b962 | 147 | // Set the PWM period, keeping the duty cycle the same. |
mbed_official | 337:6ed01c00b962 | 148 | void pwmout_period_us(pwmout_t* obj, int us) |
mbed_official | 337:6ed01c00b962 | 149 | { |
mbed_official | 337:6ed01c00b962 | 150 | uint32_t t_off = obj->pwm->MATCHREL[(obj->pwm_ch * 2) + 0]; |
mbed_official | 337:6ed01c00b962 | 151 | uint32_t t_on = obj->pwm->MATCHREL[(obj->pwm_ch * 2) + 1]; |
mbed_official | 337:6ed01c00b962 | 152 | float v = (float)t_on/(float)t_off; |
mbed_official | 516:b3fb5c6901a6 | 153 | obj->pwm->MATCHREL[(obj->pwm_ch * 2) + 0] = (uint32_t)us; |
mbed_official | 516:b3fb5c6901a6 | 154 | obj->pwm->MATCHREL[(obj->pwm_ch * 2) + 1] = (uint32_t)((float)us * (float)v); |
mbed_official | 337:6ed01c00b962 | 155 | } |
mbed_official | 337:6ed01c00b962 | 156 | |
mbed_official | 337:6ed01c00b962 | 157 | void pwmout_pulsewidth(pwmout_t* obj, float seconds) |
mbed_official | 337:6ed01c00b962 | 158 | { |
mbed_official | 337:6ed01c00b962 | 159 | pwmout_pulsewidth_us(obj, seconds * 1000000.0f); |
mbed_official | 337:6ed01c00b962 | 160 | } |
mbed_official | 337:6ed01c00b962 | 161 | |
mbed_official | 337:6ed01c00b962 | 162 | void pwmout_pulsewidth_ms(pwmout_t* obj, int ms) |
mbed_official | 337:6ed01c00b962 | 163 | { |
mbed_official | 337:6ed01c00b962 | 164 | pwmout_pulsewidth_us(obj, ms * 1000); |
mbed_official | 337:6ed01c00b962 | 165 | } |
mbed_official | 337:6ed01c00b962 | 166 | |
mbed_official | 337:6ed01c00b962 | 167 | void pwmout_pulsewidth_us(pwmout_t* obj, int us) |
mbed_official | 337:6ed01c00b962 | 168 | { |
mbed_official | 516:b3fb5c6901a6 | 169 | obj->pwm->MATCHREL[(obj->pwm_ch * 2) + 1] = (uint32_t)us; |
mbed_official | 337:6ed01c00b962 | 170 | } |
mbed_official | 337:6ed01c00b962 | 171 | |
mbed_official | 337:6ed01c00b962 | 172 | #endif |