EL4121 Embedded System / mbed-os

mbed-os

Dependents:   cobaLCDJoyMotor_Thread odometry_omni_3roda_v3 odometry_omni_3roda_v1 odometry_omni_3roda_v2 ... more

targets/TARGET_NXP/TARGET_LPC176X/rtc_api.c@0:b74591d5ab33, 2017-12-11 (annotated)

Committer:
be_bryan
Date:
Mon Dec 11 17:54:04 2017 +0000
Revision:
0:b74591d5ab33
motor ++

Who changed what in which revision?

UserRevisionLine numberNew contents of line
be_bryan 0:b74591d5ab33 1 /* mbed Microcontroller Library
be_bryan 0:b74591d5ab33 2 * Copyright (c) 2006-2013 ARM Limited
be_bryan 0:b74591d5ab33 3 *
be_bryan 0:b74591d5ab33 4 * Licensed under the Apache License, Version 2.0 (the "License");
be_bryan 0:b74591d5ab33 5 * you may not use this file except in compliance with the License.
be_bryan 0:b74591d5ab33 6 * You may obtain a copy of the License at
be_bryan 0:b74591d5ab33 7 *
be_bryan 0:b74591d5ab33 8 * http://www.apache.org/licenses/LICENSE-2.0
be_bryan 0:b74591d5ab33 9 *
be_bryan 0:b74591d5ab33 10 * Unless required by applicable law or agreed to in writing, software
be_bryan 0:b74591d5ab33 11 * distributed under the License is distributed on an "AS IS" BASIS,
be_bryan 0:b74591d5ab33 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
be_bryan 0:b74591d5ab33 13 * See the License for the specific language governing permissions and
be_bryan 0:b74591d5ab33 14 * limitations under the License.
be_bryan 0:b74591d5ab33 15 */
be_bryan 0:b74591d5ab33 16 #include "rtc_api.h"
be_bryan 0:b74591d5ab33 17 #include "mbed_mktime.h"
be_bryan 0:b74591d5ab33 18
be_bryan 0:b74591d5ab33 19 // ensure rtc is running (unchanged if already running)
be_bryan 0:b74591d5ab33 20
be_bryan 0:b74591d5ab33 21 /* Setup the RTC based on a time structure, ensuring RTC is enabled
be_bryan 0:b74591d5ab33 22 *
be_bryan 0:b74591d5ab33 23 * Can be clocked by a 32.768KHz oscillator or prescale divider based on the APB clock
be_bryan 0:b74591d5ab33 24 * - We want to use the 32khz clock, allowing for sleep mode
be_bryan 0:b74591d5ab33 25 *
be_bryan 0:b74591d5ab33 26 * Most registers are not changed by a Reset
be_bryan 0:b74591d5ab33 27 * - We must initialize these registers between power-on and setting the RTC into operation
be_bryan 0:b74591d5ab33 28
be_bryan 0:b74591d5ab33 29 * Clock Control Register
be_bryan 0:b74591d5ab33 30 * RTC_CCR[0] : Enable - 0 = Disabled, 1 = Enabled
be_bryan 0:b74591d5ab33 31 * RTC_CCR[1] : Reset - 0 = Normal, 1 = Reset
be_bryan 0:b74591d5ab33 32 * RTC_CCR[4] : Clock Source - 0 = Prescaler, 1 = 32k Xtal
be_bryan 0:b74591d5ab33 33 *
be_bryan 0:b74591d5ab33 34 * The RTC may already be running, so we should set it up
be_bryan 0:b74591d5ab33 35 * without impacting if it is the case
be_bryan 0:b74591d5ab33 36 */
be_bryan 0:b74591d5ab33 37 void rtc_init(void) {
be_bryan 0:b74591d5ab33 38 LPC_SC->PCONP |= 0x200; // Ensure power is on
be_bryan 0:b74591d5ab33 39 LPC_RTC->CCR = 0x00;
be_bryan 0:b74591d5ab33 40
be_bryan 0:b74591d5ab33 41 LPC_RTC->CCR |= 1 << 0; // Ensure the RTC is enabled
be_bryan 0:b74591d5ab33 42 }
be_bryan 0:b74591d5ab33 43
be_bryan 0:b74591d5ab33 44 void rtc_free(void) {
be_bryan 0:b74591d5ab33 45 // [TODO]
be_bryan 0:b74591d5ab33 46 }
be_bryan 0:b74591d5ab33 47
be_bryan 0:b74591d5ab33 48 /*
be_bryan 0:b74591d5ab33 49 * Little check routine to see if the RTC has been enabled
be_bryan 0:b74591d5ab33 50 *
be_bryan 0:b74591d5ab33 51 * Clock Control Register
be_bryan 0:b74591d5ab33 52 * RTC_CCR[0] : 0 = Disabled, 1 = Enabled
be_bryan 0:b74591d5ab33 53 *
be_bryan 0:b74591d5ab33 54 */
be_bryan 0:b74591d5ab33 55 int rtc_isenabled(void) {
be_bryan 0:b74591d5ab33 56 return(((LPC_RTC->CCR) & 0x01) != 0);
be_bryan 0:b74591d5ab33 57 }
be_bryan 0:b74591d5ab33 58
be_bryan 0:b74591d5ab33 59 /*
be_bryan 0:b74591d5ab33 60 * RTC Registers
be_bryan 0:b74591d5ab33 61 * RTC_SEC Seconds 0-59
be_bryan 0:b74591d5ab33 62 * RTC_MIN Minutes 0-59
be_bryan 0:b74591d5ab33 63 * RTC_HOUR Hour 0-23
be_bryan 0:b74591d5ab33 64 * RTC_DOM Day of Month 1-28..31
be_bryan 0:b74591d5ab33 65 * RTC_DOW Day of Week 0-6
be_bryan 0:b74591d5ab33 66 * RTC_DOY Day of Year 1-365
be_bryan 0:b74591d5ab33 67 * RTC_MONTH Month 1-12
be_bryan 0:b74591d5ab33 68 * RTC_YEAR Year 0-4095
be_bryan 0:b74591d5ab33 69 *
be_bryan 0:b74591d5ab33 70 * struct tm
be_bryan 0:b74591d5ab33 71 * tm_sec seconds after the minute 0-61
be_bryan 0:b74591d5ab33 72 * tm_min minutes after the hour 0-59
be_bryan 0:b74591d5ab33 73 * tm_hour hours since midnight 0-23
be_bryan 0:b74591d5ab33 74 * tm_mday day of the month 1-31
be_bryan 0:b74591d5ab33 75 * tm_mon months since January 0-11
be_bryan 0:b74591d5ab33 76 * tm_year years since 1900
be_bryan 0:b74591d5ab33 77 * tm_wday days since Sunday 0-6
be_bryan 0:b74591d5ab33 78 * tm_yday days since January 1 0-365
be_bryan 0:b74591d5ab33 79 * tm_isdst Daylight Saving Time flag
be_bryan 0:b74591d5ab33 80 */
be_bryan 0:b74591d5ab33 81 time_t rtc_read(void) {
be_bryan 0:b74591d5ab33 82 // Setup a tm structure based on the RTC
be_bryan 0:b74591d5ab33 83 struct tm timeinfo;
be_bryan 0:b74591d5ab33 84 timeinfo.tm_sec = LPC_RTC->SEC;
be_bryan 0:b74591d5ab33 85 timeinfo.tm_min = LPC_RTC->MIN;
be_bryan 0:b74591d5ab33 86 timeinfo.tm_hour = LPC_RTC->HOUR;
be_bryan 0:b74591d5ab33 87 timeinfo.tm_mday = LPC_RTC->DOM;
be_bryan 0:b74591d5ab33 88 timeinfo.tm_mon = LPC_RTC->MONTH - 1;
be_bryan 0:b74591d5ab33 89 timeinfo.tm_year = LPC_RTC->YEAR - 1900;
be_bryan 0:b74591d5ab33 90
be_bryan 0:b74591d5ab33 91 // Convert to timestamp
be_bryan 0:b74591d5ab33 92 time_t t = _rtc_mktime(&timeinfo);
be_bryan 0:b74591d5ab33 93
be_bryan 0:b74591d5ab33 94 return t;
be_bryan 0:b74591d5ab33 95 }
be_bryan 0:b74591d5ab33 96
be_bryan 0:b74591d5ab33 97 void rtc_write(time_t t) {
be_bryan 0:b74591d5ab33 98 // Convert the time in to a tm
be_bryan 0:b74591d5ab33 99 struct tm timeinfo;
be_bryan 0:b74591d5ab33 100 if (_rtc_localtime(t, &timeinfo) == false) {
be_bryan 0:b74591d5ab33 101 return;
be_bryan 0:b74591d5ab33 102 }
be_bryan 0:b74591d5ab33 103
be_bryan 0:b74591d5ab33 104 // Pause clock, and clear counter register (clears us count)
be_bryan 0:b74591d5ab33 105 LPC_RTC->CCR |= 2;
be_bryan 0:b74591d5ab33 106
be_bryan 0:b74591d5ab33 107 // Set the RTC
be_bryan 0:b74591d5ab33 108 LPC_RTC->SEC = timeinfo.tm_sec;
be_bryan 0:b74591d5ab33 109 LPC_RTC->MIN = timeinfo.tm_min;
be_bryan 0:b74591d5ab33 110 LPC_RTC->HOUR = timeinfo.tm_hour;
be_bryan 0:b74591d5ab33 111 LPC_RTC->DOM = timeinfo.tm_mday;
be_bryan 0:b74591d5ab33 112 LPC_RTC->MONTH = timeinfo.tm_mon + 1;
be_bryan 0:b74591d5ab33 113 LPC_RTC->YEAR = timeinfo.tm_year + 1900;
be_bryan 0:b74591d5ab33 114
be_bryan 0:b74591d5ab33 115 // Restart clock
be_bryan 0:b74591d5ab33 116 LPC_RTC->CCR &= ~((uint32_t)2);
be_bryan 0:b74591d5ab33 117 }