MacroRat / MouseCode

Mouse code for the MacroRat

Dependencies:   ITG3200 QEI

mbed-dev/targets/TARGET_ARM_SSG/TARGET_BEETLE/us_ticker.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) 2015 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 <stddef.h>
sahilmgandhi 18:6a4db94011d3 17 #include "cmsis.h"
sahilmgandhi 18:6a4db94011d3 18 #include "us_ticker_api.h"
sahilmgandhi 18:6a4db94011d3 19 #include "PeripheralNames.h"
sahilmgandhi 18:6a4db94011d3 20 /* Private data */
sahilmgandhi 18:6a4db94011d3 21 /* us_ticker reload value */
sahilmgandhi 18:6a4db94011d3 22 static uint32_t us_ticker_reload = 0x0; /* Max Value */
sahilmgandhi 18:6a4db94011d3 23 /* us ticker initialized */
sahilmgandhi 18:6a4db94011d3 24 static uint32_t us_ticker_inited = 0;
sahilmgandhi 18:6a4db94011d3 25 /* us ticker overflow */
sahilmgandhi 18:6a4db94011d3 26 static uint32_t us_ticker_overflow_delta = 0;
sahilmgandhi 18:6a4db94011d3 27 /* us ticker overflow limit */
sahilmgandhi 18:6a4db94011d3 28 static uint32_t us_ticker_overflow_limit = 0;
sahilmgandhi 18:6a4db94011d3 29
sahilmgandhi 18:6a4db94011d3 30 void __us_ticker_irq_handler(void) {
sahilmgandhi 18:6a4db94011d3 31 Timer_ClearInterrupt(TIMER1);
sahilmgandhi 18:6a4db94011d3 32 /*
sahilmgandhi 18:6a4db94011d3 33 * For each overflow event adds the timer max represented value to
sahilmgandhi 18:6a4db94011d3 34 * the delta. This allows the us_ticker to keep track of the elapsed
sahilmgandhi 18:6a4db94011d3 35 * time:
sahilmgandhi 18:6a4db94011d3 36 * elapsed_time = (num_overflow * overflow_limit) + current_time
sahilmgandhi 18:6a4db94011d3 37 */
sahilmgandhi 18:6a4db94011d3 38 us_ticker_overflow_delta += us_ticker_overflow_limit;
sahilmgandhi 18:6a4db94011d3 39 }
sahilmgandhi 18:6a4db94011d3 40
sahilmgandhi 18:6a4db94011d3 41 void us_ticker_init(void) {
sahilmgandhi 18:6a4db94011d3 42 uint32_t us_ticker_irqn0 = 0;
sahilmgandhi 18:6a4db94011d3 43 uint32_t us_ticker_irqn1 = 0;
sahilmgandhi 18:6a4db94011d3 44
sahilmgandhi 18:6a4db94011d3 45 if (us_ticker_inited)
sahilmgandhi 18:6a4db94011d3 46 return;
sahilmgandhi 18:6a4db94011d3 47 us_ticker_inited = 1;
sahilmgandhi 18:6a4db94011d3 48
sahilmgandhi 18:6a4db94011d3 49 /* Initialize Timer 0 */
sahilmgandhi 18:6a4db94011d3 50 Timer_Initialize(TIMER0, us_ticker_reload);
sahilmgandhi 18:6a4db94011d3 51 /* Enable Timer 0 */
sahilmgandhi 18:6a4db94011d3 52 Timer_Enable(TIMER0);
sahilmgandhi 18:6a4db94011d3 53
sahilmgandhi 18:6a4db94011d3 54 /* Initialize Timer 1 */
sahilmgandhi 18:6a4db94011d3 55 Timer_Initialize(TIMER1, us_ticker_reload);
sahilmgandhi 18:6a4db94011d3 56 /* Enable Timer 1 */
sahilmgandhi 18:6a4db94011d3 57 Timer_Enable(TIMER1);
sahilmgandhi 18:6a4db94011d3 58
sahilmgandhi 18:6a4db94011d3 59 /* Timer 0 get IRQn */
sahilmgandhi 18:6a4db94011d3 60 us_ticker_irqn0 = Timer_GetIRQn(TIMER0);
sahilmgandhi 18:6a4db94011d3 61 NVIC_SetVector((IRQn_Type)us_ticker_irqn0, (uint32_t)us_ticker_irq_handler);
sahilmgandhi 18:6a4db94011d3 62 NVIC_EnableIRQ((IRQn_Type)us_ticker_irqn0);
sahilmgandhi 18:6a4db94011d3 63
sahilmgandhi 18:6a4db94011d3 64 /* Timer 1 get IRQn */
sahilmgandhi 18:6a4db94011d3 65 us_ticker_irqn1 = Timer_GetIRQn(TIMER1);
sahilmgandhi 18:6a4db94011d3 66 NVIC_SetVector((IRQn_Type)us_ticker_irqn1, (uint32_t)__us_ticker_irq_handler);
sahilmgandhi 18:6a4db94011d3 67 NVIC_EnableIRQ((IRQn_Type)us_ticker_irqn1);
sahilmgandhi 18:6a4db94011d3 68
sahilmgandhi 18:6a4db94011d3 69 /* Timer set interrupt on TIMER1 */
sahilmgandhi 18:6a4db94011d3 70 Timer_SetInterrupt(TIMER1, TIMER_DEFAULT_RELOAD);
sahilmgandhi 18:6a4db94011d3 71
sahilmgandhi 18:6a4db94011d3 72 /*
sahilmgandhi 18:6a4db94011d3 73 * Set us_ticker Overflow limit. The us_ticker overflow limit is required
sahilmgandhi 18:6a4db94011d3 74 * to calculated the return value of the us_ticker read function in us
sahilmgandhi 18:6a4db94011d3 75 * on 32bit.
sahilmgandhi 18:6a4db94011d3 76 * A 32bit us value cannot be represented directly in the Timer Load
sahilmgandhi 18:6a4db94011d3 77 * register if it is greater than (0xFFFFFFFF ticks)/TIMER_DIVIDER_US.
sahilmgandhi 18:6a4db94011d3 78 */
sahilmgandhi 18:6a4db94011d3 79 us_ticker_overflow_limit = Timer_GetReloadValue(TIMER1);
sahilmgandhi 18:6a4db94011d3 80 }
sahilmgandhi 18:6a4db94011d3 81
sahilmgandhi 18:6a4db94011d3 82 uint32_t us_ticker_read() {
sahilmgandhi 18:6a4db94011d3 83 uint32_t return_value = 0;
sahilmgandhi 18:6a4db94011d3 84
sahilmgandhi 18:6a4db94011d3 85 if (!us_ticker_inited)
sahilmgandhi 18:6a4db94011d3 86 us_ticker_init();
sahilmgandhi 18:6a4db94011d3 87
sahilmgandhi 18:6a4db94011d3 88 return_value = us_ticker_overflow_delta + Timer_Read(TIMER1);
sahilmgandhi 18:6a4db94011d3 89
sahilmgandhi 18:6a4db94011d3 90 return return_value;
sahilmgandhi 18:6a4db94011d3 91 }
sahilmgandhi 18:6a4db94011d3 92
sahilmgandhi 18:6a4db94011d3 93 void us_ticker_set_interrupt(timestamp_t timestamp) {
sahilmgandhi 18:6a4db94011d3 94 int32_t delta = 0;
sahilmgandhi 18:6a4db94011d3 95
sahilmgandhi 18:6a4db94011d3 96 if (!us_ticker_inited)
sahilmgandhi 18:6a4db94011d3 97 us_ticker_init();
sahilmgandhi 18:6a4db94011d3 98 delta = (int32_t)(timestamp - us_ticker_read());
sahilmgandhi 18:6a4db94011d3 99 /* Check if the event was in the past */
sahilmgandhi 18:6a4db94011d3 100 if (delta <= 0) {
sahilmgandhi 18:6a4db94011d3 101 /* This event was in the past */
sahilmgandhi 18:6a4db94011d3 102 Timer_SetInterrupt(TIMER0, 0);
sahilmgandhi 18:6a4db94011d3 103 return;
sahilmgandhi 18:6a4db94011d3 104 }
sahilmgandhi 18:6a4db94011d3 105
sahilmgandhi 18:6a4db94011d3 106 /* If the event was not in the past enable interrupt */
sahilmgandhi 18:6a4db94011d3 107 Timer_SetInterrupt(TIMER0, delta);
sahilmgandhi 18:6a4db94011d3 108 }
sahilmgandhi 18:6a4db94011d3 109
sahilmgandhi 18:6a4db94011d3 110 void us_ticker_disable_interrupt(void) {
sahilmgandhi 18:6a4db94011d3 111 Timer_DisableInterrupt(TIMER0);
sahilmgandhi 18:6a4db94011d3 112 }
sahilmgandhi 18:6a4db94011d3 113
sahilmgandhi 18:6a4db94011d3 114 void us_ticker_clear_interrupt(void) {
sahilmgandhi 18:6a4db94011d3 115 Timer_ClearInterrupt(TIMER0);
sahilmgandhi 18:6a4db94011d3 116 }