From 2dfb1b743fb8eb7f8abe9bd9eea656843b693e69 Mon Sep 17 00:00:00 2001 From: Paul Staron Date: Sat, 7 Mar 2015 22:49:02 +0000 Subject: [PATCH] Added Teensy3.1 32KHz MCU loading capacitors. External loading capacitors not fitted to the Teensy3.1 PCB, Added 20pF MCU loading capacitors for 32KHz crystal. --- .../targets/hal/TARGET_Freescale/TARGET_K20XX/rtc.api.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/libraries/mbed/targets/hal/TARGET_Freescale/TARGET_K20XX/rtc.api.c b/libraries/mbed/targets/hal/TARGET_Freescale/TARGET_K20XX/rtc.api.c index 459c7b691a..d7dd1c8050 100644 --- a/libraries/mbed/targets/hal/TARGET_Freescale/TARGET_K20XX/rtc.api.c +++ b/libraries/mbed/targets/hal/TARGET_Freescale/TARGET_K20XX/rtc.api.c @@ -29,9 +29,15 @@ static void init(void) { void rtc_init(void) { init(); - + // Enable the oscillator +#if defined (TARGET_K20D50M) RTC->CR |= RTC_CR_OSCE_MASK; +#else + // Teensy3.1 requires 20pF MCU loading capacitors for 32KHz RTC oscillator + /* RTC->CR: SC2P=0,SC4P=1,SC8P=0,SC16P=1,CLKO=0,OSCE=1,UM=0,SUP=0,SPE=0,SWR=0 */ + RTC->CR |= RTC_CR_OSCE_MASK |RTC_CR_SC16P_MASK | RTC_CR_SC4P_MASK; +#endif //Configure the TSR. default value: 1 RTC->TSR = 1;