Mouse code for the MacroRat
mbed-dev/targets/TARGET_ARM_SSG/TARGET_BEETLE/lp_ticker.c@18:6a4db94011d3, 2017-05-14 (annotated)
- Committer:
- sahilmgandhi
- Date:
- Sun May 14 23:18:57 2017 +0000
- Revision:
- 18:6a4db94011d3
Publishing again
Who changed what in which revision?
User | Revision | Line number | New contents of line |
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sahilmgandhi | 18:6a4db94011d3 | 1 | /* |
sahilmgandhi | 18:6a4db94011d3 | 2 | * PackageLicenseDeclared: Apache-2.0 |
sahilmgandhi | 18:6a4db94011d3 | 3 | * Copyright (c) 2015 ARM Limited |
sahilmgandhi | 18:6a4db94011d3 | 4 | * |
sahilmgandhi | 18:6a4db94011d3 | 5 | * Licensed under the Apache License, Version 2.0 (the "License"); |
sahilmgandhi | 18:6a4db94011d3 | 6 | * you may not use this file except in compliance with the License. |
sahilmgandhi | 18:6a4db94011d3 | 7 | * You may obtain a copy of the License at |
sahilmgandhi | 18:6a4db94011d3 | 8 | * |
sahilmgandhi | 18:6a4db94011d3 | 9 | * http://www.apache.org/licenses/LICENSE-2.0 |
sahilmgandhi | 18:6a4db94011d3 | 10 | * |
sahilmgandhi | 18:6a4db94011d3 | 11 | * Unless required by applicable law or agreed to in writing, software |
sahilmgandhi | 18:6a4db94011d3 | 12 | * distributed under the License is distributed on an "AS IS" BASIS, |
sahilmgandhi | 18:6a4db94011d3 | 13 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
sahilmgandhi | 18:6a4db94011d3 | 14 | * See the License for the specific language governing permissions and |
sahilmgandhi | 18:6a4db94011d3 | 15 | * limitations under the License. |
sahilmgandhi | 18:6a4db94011d3 | 16 | */ |
sahilmgandhi | 18:6a4db94011d3 | 17 | |
sahilmgandhi | 18:6a4db94011d3 | 18 | #include "cmsis.h" |
sahilmgandhi | 18:6a4db94011d3 | 19 | #include "device.h" |
sahilmgandhi | 18:6a4db94011d3 | 20 | #include "objects.h" |
sahilmgandhi | 18:6a4db94011d3 | 21 | #include "lp_ticker_api.h" |
sahilmgandhi | 18:6a4db94011d3 | 22 | |
sahilmgandhi | 18:6a4db94011d3 | 23 | /* Private lp_ticker data */ |
sahilmgandhi | 18:6a4db94011d3 | 24 | /* lp_ticker initialize */ |
sahilmgandhi | 18:6a4db94011d3 | 25 | static uint32_t lp_ticker_initialized = 0; |
sahilmgandhi | 18:6a4db94011d3 | 26 | /* lp_ticker reload value */ |
sahilmgandhi | 18:6a4db94011d3 | 27 | static uint32_t lp_ticker_reload = 0x0; /* Max Value */ |
sahilmgandhi | 18:6a4db94011d3 | 28 | /* Store Overflow Delta */ |
sahilmgandhi | 18:6a4db94011d3 | 29 | static uint32_t lp_ticker_overflows_delta = 0; |
sahilmgandhi | 18:6a4db94011d3 | 30 | /* lp_ticker Overflow limit */ |
sahilmgandhi | 18:6a4db94011d3 | 31 | static uint32_t lp_ticker_overflow_limit = 0; |
sahilmgandhi | 18:6a4db94011d3 | 32 | |
sahilmgandhi | 18:6a4db94011d3 | 33 | #if DEVICE_LOWPOWERTIMER |
sahilmgandhi | 18:6a4db94011d3 | 34 | /** |
sahilmgandhi | 18:6a4db94011d3 | 35 | * Interrupt Handler |
sahilmgandhi | 18:6a4db94011d3 | 36 | */ |
sahilmgandhi | 18:6a4db94011d3 | 37 | void __lp_ticker_irq_handler(void) |
sahilmgandhi | 18:6a4db94011d3 | 38 | { |
sahilmgandhi | 18:6a4db94011d3 | 39 | if (DualTimer_GetIRQInfo(DUALTIMER0) == SINGLETIMER2) { |
sahilmgandhi | 18:6a4db94011d3 | 40 | DualTimer_ClearInterrupt(DUALTIMER0); |
sahilmgandhi | 18:6a4db94011d3 | 41 | /* |
sahilmgandhi | 18:6a4db94011d3 | 42 | * For each overflow event adds the timer max represented value to |
sahilmgandhi | 18:6a4db94011d3 | 43 | * the delta. This allows the lp_ticker to keep track of the elapsed |
sahilmgandhi | 18:6a4db94011d3 | 44 | * time: |
sahilmgandhi | 18:6a4db94011d3 | 45 | * elapsed_time = (num_overflow * overflow_limit) + current_time |
sahilmgandhi | 18:6a4db94011d3 | 46 | */ |
sahilmgandhi | 18:6a4db94011d3 | 47 | lp_ticker_overflows_delta += lp_ticker_overflow_limit; |
sahilmgandhi | 18:6a4db94011d3 | 48 | } else { |
sahilmgandhi | 18:6a4db94011d3 | 49 | lp_ticker_irq_handler(); |
sahilmgandhi | 18:6a4db94011d3 | 50 | } |
sahilmgandhi | 18:6a4db94011d3 | 51 | } |
sahilmgandhi | 18:6a4db94011d3 | 52 | |
sahilmgandhi | 18:6a4db94011d3 | 53 | /** |
sahilmgandhi | 18:6a4db94011d3 | 54 | * Initialize the low power ticker |
sahilmgandhi | 18:6a4db94011d3 | 55 | */ |
sahilmgandhi | 18:6a4db94011d3 | 56 | void lp_ticker_init(void) |
sahilmgandhi | 18:6a4db94011d3 | 57 | { |
sahilmgandhi | 18:6a4db94011d3 | 58 | uint32_t lp_ticker_irqn = 0; |
sahilmgandhi | 18:6a4db94011d3 | 59 | /* Verify if lp_ticker has been already Initialized */ |
sahilmgandhi | 18:6a4db94011d3 | 60 | if (lp_ticker_initialized == 1) |
sahilmgandhi | 18:6a4db94011d3 | 61 | { |
sahilmgandhi | 18:6a4db94011d3 | 62 | return; |
sahilmgandhi | 18:6a4db94011d3 | 63 | } |
sahilmgandhi | 18:6a4db94011d3 | 64 | lp_ticker_initialized = 1; |
sahilmgandhi | 18:6a4db94011d3 | 65 | |
sahilmgandhi | 18:6a4db94011d3 | 66 | /* Dualtimer Initialize */ |
sahilmgandhi | 18:6a4db94011d3 | 67 | DualTimer_Initialize(DUALTIMER0, lp_ticker_reload); |
sahilmgandhi | 18:6a4db94011d3 | 68 | /* Dualtimer Enable */ |
sahilmgandhi | 18:6a4db94011d3 | 69 | DualTimer_Enable(DUALTIMER0, DUALTIMER_COUNT_32 |
sahilmgandhi | 18:6a4db94011d3 | 70 | //| DUALTIMER_PERIODIC |
sahilmgandhi | 18:6a4db94011d3 | 71 | ); |
sahilmgandhi | 18:6a4db94011d3 | 72 | /* DualTimer get IRQn */ |
sahilmgandhi | 18:6a4db94011d3 | 73 | lp_ticker_irqn = DualTimer_GetIRQn(DUALTIMER0); |
sahilmgandhi | 18:6a4db94011d3 | 74 | /* Enable lp_ticker IRQ */ |
sahilmgandhi | 18:6a4db94011d3 | 75 | NVIC_SetVector((IRQn_Type)lp_ticker_irqn, |
sahilmgandhi | 18:6a4db94011d3 | 76 | (uint32_t)__lp_ticker_irq_handler); |
sahilmgandhi | 18:6a4db94011d3 | 77 | NVIC_EnableIRQ((IRQn_Type)lp_ticker_irqn); |
sahilmgandhi | 18:6a4db94011d3 | 78 | |
sahilmgandhi | 18:6a4db94011d3 | 79 | /* DualTimer set interrupt on SINGLETIMER2 */ |
sahilmgandhi | 18:6a4db94011d3 | 80 | DualTimer_SetInterrupt_2(DUALTIMER0, DUALTIMER_DEFAULT_RELOAD, |
sahilmgandhi | 18:6a4db94011d3 | 81 | DUALTIMER_COUNT_32 | DUALTIMER_PERIODIC); |
sahilmgandhi | 18:6a4db94011d3 | 82 | |
sahilmgandhi | 18:6a4db94011d3 | 83 | /* |
sahilmgandhi | 18:6a4db94011d3 | 84 | * Set lp_ticker Overflow limit. The lp_ticker overflow limit is required |
sahilmgandhi | 18:6a4db94011d3 | 85 | * to calculated the return value of the lp_ticker read function in us |
sahilmgandhi | 18:6a4db94011d3 | 86 | * on 32bit. |
sahilmgandhi | 18:6a4db94011d3 | 87 | * A 32bit us value cannot be represented directly in the Dual Timer Load |
sahilmgandhi | 18:6a4db94011d3 | 88 | * register if it is greater than (0xFFFFFFFF ticks)/DUALTIMER_DIVIDER_US. |
sahilmgandhi | 18:6a4db94011d3 | 89 | */ |
sahilmgandhi | 18:6a4db94011d3 | 90 | lp_ticker_overflow_limit = DualTimer_GetReloadValue(DUALTIMER0, |
sahilmgandhi | 18:6a4db94011d3 | 91 | SINGLETIMER2); |
sahilmgandhi | 18:6a4db94011d3 | 92 | } |
sahilmgandhi | 18:6a4db94011d3 | 93 | |
sahilmgandhi | 18:6a4db94011d3 | 94 | /** |
sahilmgandhi | 18:6a4db94011d3 | 95 | * Read the current counter |
sahilmgandhi | 18:6a4db94011d3 | 96 | * @return: The current timer's counter value in microseconds |
sahilmgandhi | 18:6a4db94011d3 | 97 | */ |
sahilmgandhi | 18:6a4db94011d3 | 98 | uint32_t lp_ticker_read(void) |
sahilmgandhi | 18:6a4db94011d3 | 99 | { |
sahilmgandhi | 18:6a4db94011d3 | 100 | uint32_t microseconds = 0; |
sahilmgandhi | 18:6a4db94011d3 | 101 | |
sahilmgandhi | 18:6a4db94011d3 | 102 | /* Verify if lp_ticker has not been Initialized */ |
sahilmgandhi | 18:6a4db94011d3 | 103 | if (lp_ticker_initialized == 0) |
sahilmgandhi | 18:6a4db94011d3 | 104 | lp_ticker_init(); |
sahilmgandhi | 18:6a4db94011d3 | 105 | |
sahilmgandhi | 18:6a4db94011d3 | 106 | /* Read Timer Value */ |
sahilmgandhi | 18:6a4db94011d3 | 107 | microseconds = lp_ticker_overflows_delta + DualTimer_Read_2(DUALTIMER0); |
sahilmgandhi | 18:6a4db94011d3 | 108 | |
sahilmgandhi | 18:6a4db94011d3 | 109 | return microseconds; |
sahilmgandhi | 18:6a4db94011d3 | 110 | } |
sahilmgandhi | 18:6a4db94011d3 | 111 | |
sahilmgandhi | 18:6a4db94011d3 | 112 | /** |
sahilmgandhi | 18:6a4db94011d3 | 113 | * Set interrupt for specified timestamp |
sahilmgandhi | 18:6a4db94011d3 | 114 | * timestamp: The time in microseconds to be set |
sahilmgandhi | 18:6a4db94011d3 | 115 | */ |
sahilmgandhi | 18:6a4db94011d3 | 116 | void lp_ticker_set_interrupt(timestamp_t timestamp) |
sahilmgandhi | 18:6a4db94011d3 | 117 | { |
sahilmgandhi | 18:6a4db94011d3 | 118 | int32_t delta = 0; |
sahilmgandhi | 18:6a4db94011d3 | 119 | |
sahilmgandhi | 18:6a4db94011d3 | 120 | /* Verify if lp_ticker has been not Initialized */ |
sahilmgandhi | 18:6a4db94011d3 | 121 | if (lp_ticker_initialized == 0) |
sahilmgandhi | 18:6a4db94011d3 | 122 | lp_ticker_init(); |
sahilmgandhi | 18:6a4db94011d3 | 123 | |
sahilmgandhi | 18:6a4db94011d3 | 124 | /* Calculate the delta */ |
sahilmgandhi | 18:6a4db94011d3 | 125 | delta = (int32_t)(timestamp - lp_ticker_read()); |
sahilmgandhi | 18:6a4db94011d3 | 126 | /* Check if the event was in the past */ |
sahilmgandhi | 18:6a4db94011d3 | 127 | if (delta <= 0) { |
sahilmgandhi | 18:6a4db94011d3 | 128 | /* This event was in the past */ |
sahilmgandhi | 18:6a4db94011d3 | 129 | DualTimer_SetInterrupt_1(DUALTIMER0, 0, |
sahilmgandhi | 18:6a4db94011d3 | 130 | DUALTIMER_COUNT_32 | DUALTIMER_ONESHOT); |
sahilmgandhi | 18:6a4db94011d3 | 131 | return; |
sahilmgandhi | 18:6a4db94011d3 | 132 | } |
sahilmgandhi | 18:6a4db94011d3 | 133 | |
sahilmgandhi | 18:6a4db94011d3 | 134 | /* Enable interrupt on SingleTimer1 */ |
sahilmgandhi | 18:6a4db94011d3 | 135 | DualTimer_SetInterrupt_1(DUALTIMER0, delta, |
sahilmgandhi | 18:6a4db94011d3 | 136 | DUALTIMER_COUNT_32 | DUALTIMER_ONESHOT); |
sahilmgandhi | 18:6a4db94011d3 | 137 | } |
sahilmgandhi | 18:6a4db94011d3 | 138 | |
sahilmgandhi | 18:6a4db94011d3 | 139 | /** |
sahilmgandhi | 18:6a4db94011d3 | 140 | * Disable low power ticker interrupt |
sahilmgandhi | 18:6a4db94011d3 | 141 | */ |
sahilmgandhi | 18:6a4db94011d3 | 142 | void lp_ticker_disable_interrupt(void) |
sahilmgandhi | 18:6a4db94011d3 | 143 | { |
sahilmgandhi | 18:6a4db94011d3 | 144 | /* Disable Interrupt */ |
sahilmgandhi | 18:6a4db94011d3 | 145 | DualTimer_DisableInterrupt(DUALTIMER0, |
sahilmgandhi | 18:6a4db94011d3 | 146 | SINGLETIMER1); |
sahilmgandhi | 18:6a4db94011d3 | 147 | } |
sahilmgandhi | 18:6a4db94011d3 | 148 | |
sahilmgandhi | 18:6a4db94011d3 | 149 | /** |
sahilmgandhi | 18:6a4db94011d3 | 150 | * Clear the low power ticker interrupt |
sahilmgandhi | 18:6a4db94011d3 | 151 | */ |
sahilmgandhi | 18:6a4db94011d3 | 152 | void lp_ticker_clear_interrupt(void) |
sahilmgandhi | 18:6a4db94011d3 | 153 | { |
sahilmgandhi | 18:6a4db94011d3 | 154 | /* Clear Interrupt */ |
sahilmgandhi | 18:6a4db94011d3 | 155 | DualTimer_ClearInterrupt(DUALTIMER0); |
sahilmgandhi | 18:6a4db94011d3 | 156 | } |
sahilmgandhi | 18:6a4db94011d3 | 157 | |
sahilmgandhi | 18:6a4db94011d3 | 158 | #endif |