Diff: vendor/Freescale/KL25Z/hal/rtc_api.c

Revision:

10:3bc89ef62ce7

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/vendor/Freescale/KL25Z/hal/rtc_api.c	Fri Jun 14 17:49:17 2013 +0100
@@ -0,0 +1,95 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2006-2013 ARM Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include "rtc_api.h"
+
+#if DEVICE_RTC
+
+static void init(void) {
+    // enable PORTC clock
+    SIM->SCGC5 |= SIM_SCGC5_PORTC_MASK;
+
+    // enable RTC clock
+    SIM->SCGC6 |= SIM_SCGC6_RTC_MASK;
+
+    /*
+    * configure PTC1 with alternate function 1: RTC_CLKIN
+    * As the kl25z board does not have a 32kHz osc,
+    * we use an external clock generated by the
+    * interface chip
+    */
+    PORTC->PCR[1] &= ~PORT_PCR_MUX_MASK;
+    PORTC->PCR[1] = PORT_PCR_MUX(1);
+
+    // select RTC_CLKIN as RTC clock source
+    SIM->SOPT1 &= ~SIM_SOPT1_OSC32KSEL_MASK;
+    SIM->SOPT1 |= SIM_SOPT1_OSC32KSEL(2);
+}
+
+void rtc_init(void) {
+    init();
+
+    //Configure the TSR. default value: 1
+    RTC->TSR = 1;
+
+    // enable counter
+    RTC->SR |= RTC_SR_TCE_MASK;
+}
+
+void rtc_free(void) {
+    // [TODO]
+}
+
+/*
+ * Little check routine to see if the RTC has been enabled
+ * 0 = Disabled, 1 = Enabled
+ */
+int rtc_isenabled(void) {
+    // even if the RTC module is enabled,
+    // as we use RTC_CLKIN and an external clock,
+    // we need to reconfigure the pins. That is why we
+    // call init() if the rtc is enabled
+
+    // if RTC not enabled return 0
+    SIM->SCGC5 |= SIM_SCGC5_PORTC_MASK;
+    SIM->SCGC6 |= SIM_SCGC6_RTC_MASK;
+    if ((RTC->SR & RTC_SR_TCE_MASK) == 0)
+        return 0;
+
+    init();
+    return 1;
+}
+
+time_t rtc_read(void) {
+    return RTC->TSR;
+}
+
+void rtc_write(time_t t) {
+    // disable counter
+    RTC->SR &= ~RTC_SR_TCE_MASK;
+
+    // we do not write 0 into TSR
+    // to avoid invalid time
+    if (t == 0)
+        t = 1;
+
+    // write seconds
+    RTC->TSR = t;
+
+    // re-enable counter
+    RTC->SR |= RTC_SR_TCE_MASK;
+}
+
+#endif