Morpheus / target-freescale-ksdk

Important changes to repositories hosted on mbed.com

Mbed hosted mercurial repositories are deprecated and are due to be permanently deleted in July 2026.

To keep a copy of this software download the repository Zip archive or clone locally using Mercurial.

It is also possible to export all your personal repositories from the account settings page.

Fork of target-freescale-ksdk by -deleted-

us_ticker.c@0:e4d670b91a9a, 2016-03-23 (annotated)

Committer:
screamer
Date:
Wed Mar 23 21:26:50 2016 +0000
Revision:
0:e4d670b91a9a
Initial revision

Who changed what in which revision?

UserRevisionLine numberNew contents of line
screamer 0:e4d670b91a9a 1 /* mbed Microcontroller Library
screamer 0:e4d670b91a9a 2 * Copyright (c) 2006-2013 ARM Limited
screamer 0:e4d670b91a9a 3 *
screamer 0:e4d670b91a9a 4 * Licensed under the Apache License, Version 2.0 (the "License");
screamer 0:e4d670b91a9a 5 * you may not use this file except in compliance with the License.
screamer 0:e4d670b91a9a 6 * You may obtain a copy of the License at
screamer 0:e4d670b91a9a 7 *
screamer 0:e4d670b91a9a 8 * http://www.apache.org/licenses/LICENSE-2.0
screamer 0:e4d670b91a9a 9 *
screamer 0:e4d670b91a9a 10 * Unless required by applicable law or agreed to in writing, software
screamer 0:e4d670b91a9a 11 * distributed under the License is distributed on an "AS IS" BASIS,
screamer 0:e4d670b91a9a 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
screamer 0:e4d670b91a9a 13 * See the License for the specific language governing permissions and
screamer 0:e4d670b91a9a 14 * limitations under the License.
screamer 0:e4d670b91a9a 15 */
screamer 0:e4d670b91a9a 16 #include <stddef.h>
screamer 0:e4d670b91a9a 17 #include "us_ticker_api.h"
screamer 0:e4d670b91a9a 18 #include "PeripheralNames.h"
screamer 0:e4d670b91a9a 19 #include "fsl_pit_hal.h"
screamer 0:e4d670b91a9a 20 #include "fsl_sim_hal.h"
screamer 0:e4d670b91a9a 21 #include "fsl_clock_manager.h"
screamer 0:e4d670b91a9a 22
screamer 0:e4d670b91a9a 23 static int us_ticker_inited = 0;
screamer 0:e4d670b91a9a 24
screamer 0:e4d670b91a9a 25 void us_ticker_init(void) {
screamer 0:e4d670b91a9a 26 if (us_ticker_inited) {
screamer 0:e4d670b91a9a 27 return;
screamer 0:e4d670b91a9a 28 }
screamer 0:e4d670b91a9a 29 us_ticker_inited = 1;
screamer 0:e4d670b91a9a 30
screamer 0:e4d670b91a9a 31 //Common for ticker/timer
screamer 0:e4d670b91a9a 32 uint32_t busClock;
screamer 0:e4d670b91a9a 33 CLOCK_SYS_EnablePitClock(0);
screamer 0:e4d670b91a9a 34 PIT_HAL_Enable(PIT_BASE);
screamer 0:e4d670b91a9a 35 CLOCK_SYS_GetFreq(kBusClock, &busClock);
screamer 0:e4d670b91a9a 36
screamer 0:e4d670b91a9a 37 //Timer
screamer 0:e4d670b91a9a 38 PIT_HAL_SetTimerPeriodByCount(PIT_BASE, 0, busClock / 1000000 - 1);
screamer 0:e4d670b91a9a 39 PIT_HAL_SetTimerPeriodByCount(PIT_BASE, 1, 0xFFFFFFFF);
screamer 0:e4d670b91a9a 40 PIT_HAL_SetTimerChainCmd(PIT_BASE, 1, true);
screamer 0:e4d670b91a9a 41 PIT_HAL_StartTimer(PIT_BASE, 0);
screamer 0:e4d670b91a9a 42 PIT_HAL_StartTimer(PIT_BASE, 1);
screamer 0:e4d670b91a9a 43
screamer 0:e4d670b91a9a 44 //Ticker
screamer 0:e4d670b91a9a 45 PIT_HAL_SetTimerPeriodByCount(PIT_BASE, 2, busClock / 1000000 - 1);
screamer 0:e4d670b91a9a 46 PIT_HAL_SetTimerChainCmd(PIT_BASE, 3, true);
screamer 0:e4d670b91a9a 47 NVIC_SetVector(PIT3_IRQn, (uint32_t)us_ticker_irq_handler);
screamer 0:e4d670b91a9a 48 NVIC_EnableIRQ(PIT3_IRQn);
screamer 0:e4d670b91a9a 49 }
screamer 0:e4d670b91a9a 50
screamer 0:e4d670b91a9a 51
screamer 0:e4d670b91a9a 52 uint32_t us_ticker_read() {
screamer 0:e4d670b91a9a 53 if (!us_ticker_inited) {
screamer 0:e4d670b91a9a 54 us_ticker_init();
screamer 0:e4d670b91a9a 55 }
screamer 0:e4d670b91a9a 56
screamer 0:e4d670b91a9a 57 return ~(PIT_HAL_ReadTimerCount(PIT_BASE, 1));
screamer 0:e4d670b91a9a 58 }
screamer 0:e4d670b91a9a 59
screamer 0:e4d670b91a9a 60 void us_ticker_disable_interrupt(void) {
screamer 0:e4d670b91a9a 61 PIT_HAL_SetIntCmd(PIT_BASE, 3, false);
screamer 0:e4d670b91a9a 62 }
screamer 0:e4d670b91a9a 63
screamer 0:e4d670b91a9a 64 void us_ticker_clear_interrupt(void) {
screamer 0:e4d670b91a9a 65 PIT_HAL_ClearIntFlag(PIT_BASE, 3);
screamer 0:e4d670b91a9a 66 }
screamer 0:e4d670b91a9a 67
screamer 0:e4d670b91a9a 68 void us_ticker_set_interrupt(timestamp_t timestamp) {
screamer 0:e4d670b91a9a 69 int delta = (int)(timestamp - us_ticker_read());
screamer 0:e4d670b91a9a 70 if (delta <= 0) {
screamer 0:e4d670b91a9a 71 // This event was in the past:
screamer 0:e4d670b91a9a 72 us_ticker_irq_handler();
screamer 0:e4d670b91a9a 73 return;
screamer 0:e4d670b91a9a 74 }
screamer 0:e4d670b91a9a 75
screamer 0:e4d670b91a9a 76 PIT_HAL_StopTimer(PIT_BASE, 3);
screamer 0:e4d670b91a9a 77 PIT_HAL_StopTimer(PIT_BASE, 2);
screamer 0:e4d670b91a9a 78 PIT_HAL_SetTimerPeriodByCount(PIT_BASE, 3, (uint32_t)delta);
screamer 0:e4d670b91a9a 79 PIT_HAL_SetIntCmd(PIT_BASE, 3, true);
screamer 0:e4d670b91a9a 80 PIT_HAL_StartTimer(PIT_BASE, 3);
screamer 0:e4d670b91a9a 81 PIT_HAL_StartTimer(PIT_BASE, 2);
screamer 0:e4d670b91a9a 82 }