Johannes Stratmann / mbed-dev

added prescaler for 16 bit pwm in LPC1347 target

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targets/cmsis/TARGET_ARM_SSG/TARGET_BEETLE/systick_timer.c@144:ef7eb2e8f9f7, 2016-09-02 (annotated)

Committer:
<>
Date:
Fri Sep 02 15:07:44 2016 +0100
Revision:
144:ef7eb2e8f9f7
This updates the lib to the mbed lib v125

Who changed what in which revision?

UserRevisionLine numberNew contents of line
<> 144:ef7eb2e8f9f7 1 /*
<> 144:ef7eb2e8f9f7 2 * PackageLicenseDeclared: Apache-2.0
<> 144:ef7eb2e8f9f7 3 * Copyright (c) 2015 ARM Limited
<> 144:ef7eb2e8f9f7 4 *
<> 144:ef7eb2e8f9f7 5 * Licensed under the Apache License, Version 2.0 (the "License");
<> 144:ef7eb2e8f9f7 6 * you may not use this file except in compliance with the License.
<> 144:ef7eb2e8f9f7 7 * You may obtain a copy of the License at
<> 144:ef7eb2e8f9f7 8 *
<> 144:ef7eb2e8f9f7 9 * http://www.apache.org/licenses/LICENSE-2.0
<> 144:ef7eb2e8f9f7 10 *
<> 144:ef7eb2e8f9f7 11 * Unless required by applicable law or agreed to in writing, software
<> 144:ef7eb2e8f9f7 12 * distributed under the License is distributed on an "AS IS" BASIS,
<> 144:ef7eb2e8f9f7 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
<> 144:ef7eb2e8f9f7 14 * See the License for the specific language governing permissions and
<> 144:ef7eb2e8f9f7 15 * limitations under the License.
<> 144:ef7eb2e8f9f7 16 */
<> 144:ef7eb2e8f9f7 17
<> 144:ef7eb2e8f9f7 18 #include "cmsis.h"
<> 144:ef7eb2e8f9f7 19 #include "systick_timer.h"
<> 144:ef7eb2e8f9f7 20
<> 144:ef7eb2e8f9f7 21 volatile uint32_t MyTicks;
<> 144:ef7eb2e8f9f7 22
<> 144:ef7eb2e8f9f7 23 /* Private Data SysTick */
<> 144:ef7eb2e8f9f7 24 static uint32_t clock;
<> 144:ef7eb2e8f9f7 25
<> 144:ef7eb2e8f9f7 26 /*
<> 144:ef7eb2e8f9f7 27 * This Timer is written for MBED OS so the interrupt
<> 144:ef7eb2e8f9f7 28 * is used to keep track of the overflow.
<> 144:ef7eb2e8f9f7 29 */
<> 144:ef7eb2e8f9f7 30 #define SYSTICK_MAX_RELOAD 0xFFFFFFFF
<> 144:ef7eb2e8f9f7 31 #define SYSTICK_DIVIDER_US (SystemCoreClock/1000000)
<> 144:ef7eb2e8f9f7 32
<> 144:ef7eb2e8f9f7 33 void SysTick_IRQ_Handler(void)
<> 144:ef7eb2e8f9f7 34 {
<> 144:ef7eb2e8f9f7 35 MyTicks++;
<> 144:ef7eb2e8f9f7 36 #if 0
<> 144:ef7eb2e8f9f7 37 printf("System Tick Interrupt: %u\n\r", MyTicks);
<> 144:ef7eb2e8f9f7 38 #endif
<> 144:ef7eb2e8f9f7 39 }
<> 144:ef7eb2e8f9f7 40
<> 144:ef7eb2e8f9f7 41 /*
<> 144:ef7eb2e8f9f7 42 * SysTick_Initialize(): Initializes the SysTick timer
<> 144:ef7eb2e8f9f7 43 */
<> 144:ef7eb2e8f9f7 44 void SysTick_Initialize(void)
<> 144:ef7eb2e8f9f7 45 {
<> 144:ef7eb2e8f9f7 46 clock = SYSTICK_MAX_RELOAD;
<> 144:ef7eb2e8f9f7 47 #if 0
<> 144:ef7eb2e8f9f7 48 printf("\n\rEnable System Tick Interrupt...\n\r");
<> 144:ef7eb2e8f9f7 49 #endif
<> 144:ef7eb2e8f9f7 50 MyTicks=0;
<> 144:ef7eb2e8f9f7 51
<> 144:ef7eb2e8f9f7 52 /* SysTick Reload Value Register */
<> 144:ef7eb2e8f9f7 53 SysTick->LOAD = clock;
<> 144:ef7eb2e8f9f7 54
<> 144:ef7eb2e8f9f7 55 /*
<> 144:ef7eb2e8f9f7 56 * SysTick_CTRL_CLKSOURCE_Msk : Use core's clock
<> 144:ef7eb2e8f9f7 57 * SysTick_CTRL_ENABLE_Msk : Enable SysTick
<> 144:ef7eb2e8f9f7 58 * SysTick_CTRL_TICKINT_Msk : Active the SysTick interrupt on the NVIC
<> 144:ef7eb2e8f9f7 59 */
<> 144:ef7eb2e8f9f7 60 SysTick->CTRL = SysTick_CTRL_CLKSOURCE_Msk
<> 144:ef7eb2e8f9f7 61 | SysTick_CTRL_ENABLE_Msk
<> 144:ef7eb2e8f9f7 62 | SysTick_CTRL_TICKINT_Msk;
<> 144:ef7eb2e8f9f7 63
<> 144:ef7eb2e8f9f7 64 /* Register the Interrupt */
<> 144:ef7eb2e8f9f7 65 NVIC_SetVector(SysTick_IRQn, (uint32_t)SysTick_IRQ_Handler);
<> 144:ef7eb2e8f9f7 66 NVIC_EnableIRQ(SysTick_IRQn);
<> 144:ef7eb2e8f9f7 67 }
<> 144:ef7eb2e8f9f7 68
<> 144:ef7eb2e8f9f7 69 /*
<> 144:ef7eb2e8f9f7 70 * SysTick_Disable(): Disables the SysTick timer
<> 144:ef7eb2e8f9f7 71 */
<> 144:ef7eb2e8f9f7 72 void SysTick_Disable(void)
<> 144:ef7eb2e8f9f7 73 {
<> 144:ef7eb2e8f9f7 74 /* Disable SysTick */
<> 144:ef7eb2e8f9f7 75 SysTick->CTRL = 0;
<> 144:ef7eb2e8f9f7 76 }
<> 144:ef7eb2e8f9f7 77
<> 144:ef7eb2e8f9f7 78 /*
<> 144:ef7eb2e8f9f7 79 * SysTick_Read(): Read SysTick Value
<> 144:ef7eb2e8f9f7 80 * @return: the SysTick VALUE
<> 144:ef7eb2e8f9f7 81 */
<> 144:ef7eb2e8f9f7 82 uint32_t SysTick_Read(void)
<> 144:ef7eb2e8f9f7 83 {
<> 144:ef7eb2e8f9f7 84 return ((clock - (SysTick->VAL)) / SYSTICK_DIVIDER_US);
<> 144:ef7eb2e8f9f7 85 }
<> 144:ef7eb2e8f9f7 86
<> 144:ef7eb2e8f9f7 87 /*
<> 144:ef7eb2e8f9f7 88 * SysTick_Overflow(): Read SysTick Overflow Value
<> 144:ef7eb2e8f9f7 89 * @return: the SysTick Overflow VALUE
<> 144:ef7eb2e8f9f7 90 */
<> 144:ef7eb2e8f9f7 91 uint32_t SysTick_Overflow(void)
<> 144:ef7eb2e8f9f7 92 {
<> 144:ef7eb2e8f9f7 93 return MyTicks;
<> 144:ef7eb2e8f9f7 94 }