rtctempcompensation.h

MSP430 RTC temperature compensation

/*
 *  Project                     MSP430 RTC Temperature Compensation
 *
 *  Software Name               FLASH-resident Main Application Software
 *
 *  Software Part Number        tbd
 *
 *  Module Filename             RtcTempCompensation.h
 *
 *  Module Description          RTC Temperature Compensation Header File
 *
 *  Module Language             ANSI C
 *
 *  Start Date                  13/10/2004      WH Molesworth   Initialed:
 *
 *  Check Date                  --/--/----      -               Initialed:
 *
 *  Last Code Mod. Date         09/10/2006      WH Molesworth   Initialed:
 *
 *  Revision Status             Version 1.00    (See Revision History below)
 *
 *  Manufacturer:               TI (Retro Watch Development Kit)
 *                              <www.ti.com>
 *
 *  Author:                     Hugh Molesworth    [e-mail]
 *                              Tel. US [phone]
 *
 *  Source by Hugh Molesworth. All Rights Reserved. Provided for guidance,
 *  feel free to use provided this notice is included.
 *
 *  Revision History:
 *  =================
 *
 *   Evaluation Release for TI MSP430 Design Contest
 *   ===============================================
 *   HM 00.01 09/10/2006 - Initial Release
 */

#ifndef RTC_COMPENSATION_H
#define RTC_COMPENSATION_H

#define OPTION_USING_TEMPERATURE_COMPENSATION_FOR_RTC
#define OPTION_USING_TIMERA_3_FOR_RTC

// The error correction of +3 is for about +12.5 seconds of error in 38hrs 17mins
// Error reduced to -1 second in 48 hours using 3, so use 2 + delta
// ie total unadjusted error approx 14.67 seconds per 48 hours -> 2.78187 -> 2 plus 47 counts/minute
#define TIMER_A_RESET_TIME (32767+2)  // (32768-1) 1 second tick @ 32.768KHz plus error
#define TIMER_A_DELTA_TIME  (47)       // delta adjust every minute (add this to temp correction)

typedef unsigned char  byte;
typedef unsigned short uint16;
typedef          short sint16;
typedef unsigned long  uint32;
typedef          long  sint32;

#if defined (OPTION_USING_TEMPERATURE_COMPENSATION_FOR_RTC)
   #define MIN_RTC_CALIBRATION_TEMP    (-40)  // degrees C, lowest value
   #define CENTER_RTC_CALIBRATION_TEMP ( 25)  // degrees C, zero cal value
   #define MAX_RTC_CALIBRATION_TEMP    ( 90)  // degrees C, maximum value
   // zero cal index at (typically) 25 degrees C
   #define CENTER_RTC_CALIBRATION_INDEX (CENTER_RTC_CALIBRATION_TEMP-MIN_RTC_CALIBRATION_TEMP)

    // The raw ADC Temperature value for the later compensation
   extern uint16 SampledAdcRawValue;

   extern volatile byte UpdateTempCorrectionFlag;

   extern const byte FrequencyCorrectionTable[];

   // Initialize RTC temperature cal index at (typically) 25 degrees C
   extern uint16 RtcCorrectionTime;
   //volatile byte RtcCorrectionIndex = CENTER_RTC_CALIBRATION_INDEX;

   void UpdateCorrection(void);
   void InitialiseTimerA1(void);

#endif

#endif //#ifndef RTC_COMPENSATION_H