Tomo Yamanaka / mbed-dev

mbed library sources. Supersedes mbed-src. GR-PEACH runs on RAM.

Fork of mbed-dev by mbed official

targets/hal/TARGET_NXP/TARGET_LPC23XX/rtc_api.c@103:493a29d2d4d7, 2016-03-30 (annotated)

Committer:
1050186
Date:
Wed Mar 30 11:41:25 2016 +0000
Revision:
103:493a29d2d4d7
Parent:
0:9b334a45a8ff 
GR-PEACH runs on RAM.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
bogdanm 0:9b334a45a8ff 1 /* mbed Microcontroller Library
bogdanm 0:9b334a45a8ff 2 * Copyright (c) 2006-2013 ARM Limited
bogdanm 0:9b334a45a8ff 3 *
bogdanm 0:9b334a45a8ff 4 * Licensed under the Apache License, Version 2.0 (the "License");
bogdanm 0:9b334a45a8ff 5 * you may not use this file except in compliance with the License.
bogdanm 0:9b334a45a8ff 6 * You may obtain a copy of the License at
bogdanm 0:9b334a45a8ff 7 *
bogdanm 0:9b334a45a8ff 8 * http://www.apache.org/licenses/LICENSE-2.0
bogdanm 0:9b334a45a8ff 9 *
bogdanm 0:9b334a45a8ff 10 * Unless required by applicable law or agreed to in writing, software
bogdanm 0:9b334a45a8ff 11 * distributed under the License is distributed on an "AS IS" BASIS,
bogdanm 0:9b334a45a8ff 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
bogdanm 0:9b334a45a8ff 13 * See the License for the specific language governing permissions and
bogdanm 0:9b334a45a8ff 14 * limitations under the License.
bogdanm 0:9b334a45a8ff 15 */
bogdanm 0:9b334a45a8ff 16 #include "rtc_api.h"
bogdanm 0:9b334a45a8ff 17
bogdanm 0:9b334a45a8ff 18 // ensure rtc is running (unchanged if already running)
bogdanm 0:9b334a45a8ff 19
bogdanm 0:9b334a45a8ff 20 /* Setup the RTC based on a time structure, ensuring RTC is enabled
bogdanm 0:9b334a45a8ff 21 *
bogdanm 0:9b334a45a8ff 22 * Can be clocked by a 32.768KHz oscillator or prescale divider based on the APB clock
bogdanm 0:9b334a45a8ff 23 * - We want to use the 32khz clock, allowing for sleep mode
bogdanm 0:9b334a45a8ff 24 *
bogdanm 0:9b334a45a8ff 25 * Most registers are not changed by a Reset
bogdanm 0:9b334a45a8ff 26 * - We must initialize these registers between power-on and setting the RTC into operation
bogdanm 0:9b334a45a8ff 27
bogdanm 0:9b334a45a8ff 28 * Clock Control Register
bogdanm 0:9b334a45a8ff 29 * RTC_CCR[0] : Enable - 0 = Disabled, 1 = Enabled
bogdanm 0:9b334a45a8ff 30 * RTC_CCR[1] : Reset - 0 = Normal, 1 = Reset
bogdanm 0:9b334a45a8ff 31 * RTC_CCR[4] : Clock Source - 0 = Prescaler, 1 = 32k Xtal
bogdanm 0:9b334a45a8ff 32 *
bogdanm 0:9b334a45a8ff 33 * The RTC may already be running, so we should set it up
bogdanm 0:9b334a45a8ff 34 * without impacting if it is the case
bogdanm 0:9b334a45a8ff 35 */
bogdanm 0:9b334a45a8ff 36 void rtc_init(void) {
bogdanm 0:9b334a45a8ff 37 LPC_SC->PCONP |= 0x200; // Ensure power is on
bogdanm 0:9b334a45a8ff 38 LPC_RTC->CCR = 0x00;
bogdanm 0:9b334a45a8ff 39
bogdanm 0:9b334a45a8ff 40 // clock source on 2368 is special test mode on 1768!
bogdanm 0:9b334a45a8ff 41 LPC_RTC->CCR |= 1 << 4; // Ensure clock source is 32KHz Xtal
bogdanm 0:9b334a45a8ff 42
bogdanm 0:9b334a45a8ff 43 LPC_RTC->CCR |= 1 << 0; // Ensure the RTC is enabled
bogdanm 0:9b334a45a8ff 44 }
bogdanm 0:9b334a45a8ff 45
bogdanm 0:9b334a45a8ff 46 void rtc_free(void) {
bogdanm 0:9b334a45a8ff 47 // [TODO]
bogdanm 0:9b334a45a8ff 48 }
bogdanm 0:9b334a45a8ff 49
bogdanm 0:9b334a45a8ff 50 /*
bogdanm 0:9b334a45a8ff 51 * Little check routine to see if the RTC has been enabled
bogdanm 0:9b334a45a8ff 52 *
bogdanm 0:9b334a45a8ff 53 * Clock Control Register
bogdanm 0:9b334a45a8ff 54 * RTC_CCR[0] : 0 = Disabled, 1 = Enabled
bogdanm 0:9b334a45a8ff 55 *
bogdanm 0:9b334a45a8ff 56 */
bogdanm 0:9b334a45a8ff 57
bogdanm 0:9b334a45a8ff 58 int rtc_isenabled(void) {
bogdanm 0:9b334a45a8ff 59 return(((LPC_RTC->CCR) & 0x01) != 0);
bogdanm 0:9b334a45a8ff 60 }
bogdanm 0:9b334a45a8ff 61
bogdanm 0:9b334a45a8ff 62 /*
bogdanm 0:9b334a45a8ff 63 * RTC Registers
bogdanm 0:9b334a45a8ff 64 * RTC_SEC Seconds 0-59
bogdanm 0:9b334a45a8ff 65 * RTC_MIN Minutes 0-59
bogdanm 0:9b334a45a8ff 66 * RTC_HOUR Hour 0-23
bogdanm 0:9b334a45a8ff 67 * RTC_DOM Day of Month 1-28..31
bogdanm 0:9b334a45a8ff 68 * RTC_DOW Day of Week 0-6
bogdanm 0:9b334a45a8ff 69 * RTC_DOY Day of Year 1-365
bogdanm 0:9b334a45a8ff 70 * RTC_MONTH Month 1-12
bogdanm 0:9b334a45a8ff 71 * RTC_YEAR Year 0-4095
bogdanm 0:9b334a45a8ff 72 *
bogdanm 0:9b334a45a8ff 73 * struct tm
bogdanm 0:9b334a45a8ff 74 * tm_sec seconds after the minute 0-61
bogdanm 0:9b334a45a8ff 75 * tm_min minutes after the hour 0-59
bogdanm 0:9b334a45a8ff 76 * tm_hour hours since midnight 0-23
bogdanm 0:9b334a45a8ff 77 * tm_mday day of the month 1-31
bogdanm 0:9b334a45a8ff 78 * tm_mon months since January 0-11
bogdanm 0:9b334a45a8ff 79 * tm_year years since 1900
bogdanm 0:9b334a45a8ff 80 * tm_wday days since Sunday 0-6
bogdanm 0:9b334a45a8ff 81 * tm_yday days since January 1 0-365
bogdanm 0:9b334a45a8ff 82 * tm_isdst Daylight Saving Time flag
bogdanm 0:9b334a45a8ff 83 */
bogdanm 0:9b334a45a8ff 84 time_t rtc_read(void) {
bogdanm 0:9b334a45a8ff 85 // Setup a tm structure based on the RTC
bogdanm 0:9b334a45a8ff 86 struct tm timeinfo;
bogdanm 0:9b334a45a8ff 87 timeinfo.tm_sec = LPC_RTC->SEC;
bogdanm 0:9b334a45a8ff 88 timeinfo.tm_min = LPC_RTC->MIN;
bogdanm 0:9b334a45a8ff 89 timeinfo.tm_hour = LPC_RTC->HOUR;
bogdanm 0:9b334a45a8ff 90 timeinfo.tm_mday = LPC_RTC->DOM;
bogdanm 0:9b334a45a8ff 91 timeinfo.tm_mon = LPC_RTC->MONTH - 1;
bogdanm 0:9b334a45a8ff 92 timeinfo.tm_year = LPC_RTC->YEAR - 1900;
bogdanm 0:9b334a45a8ff 93
bogdanm 0:9b334a45a8ff 94 // Convert to timestamp
bogdanm 0:9b334a45a8ff 95 time_t t = mktime(&timeinfo);
bogdanm 0:9b334a45a8ff 96
bogdanm 0:9b334a45a8ff 97 return t;
bogdanm 0:9b334a45a8ff 98 }
bogdanm 0:9b334a45a8ff 99
bogdanm 0:9b334a45a8ff 100 void rtc_write(time_t t) {
bogdanm 0:9b334a45a8ff 101 // Convert the time in to a tm
bogdanm 0:9b334a45a8ff 102 struct tm *timeinfo = localtime(&t);
bogdanm 0:9b334a45a8ff 103
bogdanm 0:9b334a45a8ff 104 // Pause clock, and clear counter register (clears us count)
bogdanm 0:9b334a45a8ff 105 LPC_RTC->CCR |= 2;
bogdanm 0:9b334a45a8ff 106
bogdanm 0:9b334a45a8ff 107 // Set the RTC
bogdanm 0:9b334a45a8ff 108 LPC_RTC->SEC = timeinfo->tm_sec;
bogdanm 0:9b334a45a8ff 109 LPC_RTC->MIN = timeinfo->tm_min;
bogdanm 0:9b334a45a8ff 110 LPC_RTC->HOUR = timeinfo->tm_hour;
bogdanm 0:9b334a45a8ff 111 LPC_RTC->DOM = timeinfo->tm_mday;
bogdanm 0:9b334a45a8ff 112 LPC_RTC->MONTH = timeinfo->tm_mon + 1;
bogdanm 0:9b334a45a8ff 113 LPC_RTC->YEAR = timeinfo->tm_year + 1900;
bogdanm 0:9b334a45a8ff 114
bogdanm 0:9b334a45a8ff 115 // Restart clock
bogdanm 0:9b334a45a8ff 116 LPC_RTC->CCR &= ~((uint32_t)2);
bogdanm 0:9b334a45a8ff 117 }