Diff: ISL1208.h

Revision:

0:697ca602e934

Child:

1:c951ff6da740

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ISL1208.h	Mon Sep 09 19:32:41 2013 +0000
@@ -0,0 +1,341 @@
+/* ISL1208 Driver Library
+ * Copyright (c) 2013 Neil Thiessen
+ *
+ * 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.
+ */
+
+#ifndef ISL1208_H
+#define ISL1208_H
+
+#include "mbed.h"
+
+/** ISL1208 class.
+ *  Used for controlling an ISL1208 real time clock connected via I2C.
+ *
+ * Example:
+ * @code
+ * #include "mbed.h"
+ * #include "ISL1208.h"
+ *
+ * ISL1208 rtc(p28, p27);
+ *
+ * int main()
+ * {
+ *     //Try to open the ISL1208
+ *     if (rtc.open(ISL1208::OSCILLATOR_CRYSTAL)) {
+ *         printf("Device detected!\n");
+ *
+ *         //Check if we need to reset the time
+ *         if (rtc.powerFailed()) {
+ *             //The time has been lost due to a power complete power failure
+ *             printf("Device has lost power! Resetting time...\n");
+ *
+ *             //Set RTC time to Wed, 28 Oct 2009 11:35:37
+ *             rtc.time(1256729737);
+ *         }
+ *
+ *         while(1) {
+ *             //Get the current time
+ *             time_t seconds = rtc.time();
+ *
+ *             //Print the time in various formats
+ *             printf("\nTime as seconds since January 1, 1970 = %d\n", seconds);
+ *             printf("Time as a basic string = %s", ctime(&seconds));
+ *             char buffer[32];
+ *             strftime(buffer, 32, "%I:%M %p\n", localtime(&seconds));
+ *             printf("Time as a custom formatted string = %s", buffer);
+ *
+ *             //Delay for 1.0 seconds
+ *             wait(1.0);
+ *         }
+ *     } else {
+ *         printf("Device not detected!\n");
+ *     }
+ * }
+ * @endcode
+ */
+class ISL1208
+{
+public:
+    /** Represents the different oscillator modes for the ISL1208
+     */
+    enum OscillatorMode {
+        OSCILLATOR_CRYSTAL,  /**< The internal crystal oscillator is enabled */
+        OSCILLATOR_EXTERNAL  /**< The internal crystal oscillator is disabled, an external 32kHz oscillator is connected to X1 */
+    };
+
+    /** Represents the different output frequencies for the IRQ/fOUT pin on the ISL1208
+     */
+    enum OutputFrequency {
+        FOUT_DISABLED = 0,  /**< Disable frequency generation on the IRQ/fOUT pin */
+        FOUT_32768_HZ,      /**< Generate 32.768kHz on the IRQ/fOUT pin */
+        FOUT_4096_HZ,       /**< Generate 4.096kHz on the IRQ/fOUT pin */
+        FOUT_1024_HZ,       /**< Generate 1.024kHz on the IRQ/fOUT pin */
+        FOUT_64_HZ,         /**< Generate 64Hz on the IRQ/fOUT pin */
+        FOUT_32_HZ,         /**< Generate 32Hz on the IRQ/fOUT pin */
+        FOUT_16_HZ,         /**< Generate 16Hz on the IRQ/fOUT pin */
+        FOUT_8_HZ,          /**< Generate 8Hz on the IRQ/fOUT pin */
+        FOUT_4_HZ,          /**< Generate 4Hz on the IRQ/fOUT pin */
+        FOUT_2_HZ,          /**< Generate 2Hz on the IRQ/fOUT pin */
+        FOUT_1_HZ,          /**< Generate 1Hz on the IRQ/fOUT pin */
+        FOUT_1_2_HZ,        /**< Generate 1/2Hz on the IRQ/fOUT pin */
+        FOUT_1_4_HZ,        /**< Generate 1/4Hz on the IRQ/fOUT pin */
+        FOUT_1_8_HZ,        /**< Generate 1/8Hz on the IRQ/fOUT pin */
+        FOUT_1_16_HZ,       /**< Generate 1/16Hz on the IRQ/fOUT pin */
+        FOUT_1_32_HZ        /**< Generate 1/32Hz on the IRQ/fOUT pin */
+    };
+
+    /** Represents the power mode of the ISL1208
+     */
+    enum PowerMode {
+        POWER_NORMAL,   /**< VBAT supply will be used when VDD < VBAT - VBATHYS and VDD < VTRIP */
+        POWER_LPMODE    /**< VBAT supply will be used when VDD < VBAT - VBATHYS */
+    };
+
+    /** Represents the alarm mode of the ISL1208
+     */
+    enum AlarmMode {
+        ALARM_DISABLED, /**< The alarm function is disabled */
+        ALARM_SINGLE,   /**< Only a one-time match will be made between the RTC and alarm registers, and the IRQ/fOUT pin will pull low until the alarm flag is cleared */
+        ALARM_INTERRUPT /**< Every time an alarm match is made the IRQ/fOUT pin will pull low for 250ms, the alarm flag does not have to be cleared */
+    };
+
+    /** Represents the different battery mode ATR selections of the ISL1208
+     */
+    enum BatteryModeATR {
+        BMATR_ZERO = 0,     /**< Delta capacitance = 0pF */
+        BMATR_MINUS_0_5,    /**< Delta capacitance = -0.5pF (≈ +2ppm) */
+        BMATR_PLUS_0_5,     /**< Delta capacitance = +0.5pF (≈ -2ppm) */
+        BMATR_PLUS_1_0      /**< Delta capacitance = +1pF (≈ -4ppm) */
+    };
+
+    /** Represents the different digital trim selections of the ISL1208
+     */
+    enum DigitalTrim {
+        DTR_ZERO = 0,       /**< Digital trim = 0ppm */
+        DTR_PLUS_20,        /**< Digital trim = ≈ +20ppm */
+        DTR_PLUS_40,        /**< Digital trim = ≈ +40ppm */
+        DTR_PLUS_60,        /**< Digital trim = ≈ +60ppm */
+        DTR_MINUS_20 = 5,   /**< Digital trim = ≈ -20ppm */
+        DTR_MINUS_40,       /**< Digital trim = ≈ -40ppm */
+        DTR_MINUS_60        /**< Digital trim = ≈ -60ppm */
+    };
+
+    /** Create a ISL1208 object connected to the specified I2C pins
+     *
+     * @param sda The I2C data pin.
+     * @param scl The I2C clock pin.
+     */
+    ISL1208(PinName sda, PinName scl);
+
+    /** Probe for the ISL1208 and configures the oscillator mode if present
+     *
+     * @param mode The oscillator mode.
+     * @returns
+     *   'true' if the device exists on the bus,
+     *   'false' if the device doesn't exist on the bus.
+     */
+    bool open(OscillatorMode mode);
+
+    /** Get the current time from the ISL1208
+     *
+     * @returns The current time as a Unix timestamp.
+     */
+    time_t time(void);
+
+    /** Set the current time on the ISL1208 from a Unix timestamp
+     *
+     * @param t The current time as a Unix timestamp.
+     */
+    void time(time_t t);
+
+    /** Determine whether the RTC has completely lost power (and hence the time and SRAM)
+     *
+     * @returns Whether or not the RTC has completely lost power.
+     */
+    bool powerFailed(void);
+
+    /** Determine whether the RTC has been on battery backup
+     *
+     * @returns Whether or not the RTC has been on battery backup.
+     */
+    bool batteryFlag(void);
+
+    /** Clear the battery backup flag
+     */
+    void clearBatteryFlag(void);
+
+    /** Determine whether the alarm has matched the RTC
+     *
+     * @returns Whether or not the alarm has matched the RTC.
+     */
+    bool alarmFlag(void);
+
+    /** Clear the alarm flag
+     */
+    void clearAlarmFlag(void);
+
+    /** Get the current output frequency on the IRQ/fOUT pin
+     *
+     * @returns The current output frequency.
+     */
+    ISL1208::OutputFrequency foutFrequency(void);
+
+    /** Set the output frequency on the IRQ/fOUT pin
+     *
+     * @param freq The new output frequency.
+     */
+    void foutFrequency(OutputFrequency freq);
+
+    /** Determine whether or not the IRQ/fOUT pin will continue to output on battery power
+     *
+     * @returns Whether or not the IRQ/fOUT pin will continue to output on battery power.
+     */
+    bool outputOnBattery(void);
+
+    /** Set whether or not the IRQ/fOUT pin should continue to output on battery power
+     *
+     * @param output Whether or not the IRQ/fOUT pin should continue to output on battery power.
+     */
+    void outputOnBattery(bool output);
+
+    /** Get the current power mode of the ISL1208
+     *
+     * @returns The current power mode as a PowerMode enum.
+     */
+    ISL1208::PowerMode powerMode(void);
+
+    /** Set the power mode of the ISL1208
+     *
+     * @param mode The new power mode as a PowerMode enum.
+     */
+    void powerMode(PowerMode mode);
+
+    /** Get the current alarm mode of the ISL1208
+     *
+     * @returns The current alarm mode as an AlarmMode enum.
+     */
+    ISL1208::AlarmMode alarmMode(void);
+
+    /** Set the alarm mode of the ISL1208
+     *
+     * @param mode The new alarm mode as an AlarmMode enum.
+     */
+    void alarmMode(AlarmMode mode);
+
+    /** Get the current analog trim of the ISL1208
+     *
+     * @returns The current analog trim in pF.
+     */
+    float analogTrim(void);
+
+    /** Set the analog trim of the ISL1208
+     *
+     * @param trim The new analog trim in pF (valid range 4.5pF to 20.25pF in 0.25pF steps).
+     */
+    void analogTrim(float trim);
+
+    /** Get the current battery mode analog trim of the ISL1208
+     *
+     * @returns The current battery mode analog trim as a BatteryModeATR enum.
+     */
+    ISL1208::BatteryModeATR batteryModeATR(void);
+
+    /** Set the battery mode analog trim of the ISL1208
+     *
+     * @param mode The new battery mode analog trim as a BatteryModeATR enum.
+     */
+    void batteryModeATR(BatteryModeATR atr);
+
+    /** Get the current digital trim of the ISL1208
+     *
+     * @returns The current digital trim as a DigitalTrim enum.
+     */
+    ISL1208::DigitalTrim digitalTrim(void);
+
+    /** Set the digital trim of the ISL1208
+     *
+     * @param mode The new digital trim as a DigitalTrim enum.
+     */
+    void digitalTrim(DigitalTrim dtr);
+
+    /** Get the alarm time from the ISL1208
+     *
+     * @returns The current alarm time as a Unix timestamp (with the current year)
+     */
+    time_t alarmTime(void);
+
+    /** Set the alarm time on the ISL1208 from a Unix timestamp
+     *
+     * @param t The alarm time as a Unix timestamp.
+     * @param sc Enable or disable seconds matching.
+     * @param mn Enable or disable minutes matching.
+     * @param hr Enable or disable hours matching.
+     * @param dt Enable or disable date matching.
+     * @param mo Enable or disable month matching.
+     * @param dw Enable or disable day of week matching.
+     */
+    void alarmTime(time_t t, bool sc = true, bool mn = true, bool hr = true, bool dt = true, bool mo = true, bool dw = true);
+
+    /** Read the contents of the battery-backed SRAM
+     *
+     * @returns The current contents of the SRAM.
+     */
+    unsigned short sram(void);
+
+    /** Write new data to the battery-backed SRAM
+     *
+     * @param data The new data for the SRAM.
+     */
+    void sram(unsigned short data);
+
+private:
+    //I2C register addresses
+    enum Register {
+        REG_RTC_SC  = 0x00,
+        REG_RTC_MN,
+        REG_RTC_HR,
+        REG_RTC_DT,
+        REG_RTC_MO,
+        REG_RTC_YR,
+        REG_RTC_DW,
+        REG_CTL_SR,
+        REG_CTL_INT,
+        REG_CTL_ATR = 0x0A,
+        REG_CTL_DTR,
+        REG_ALM_SCA,
+        REG_ALM_MNA,
+        REG_ALM_HRA,
+        REG_ALM_DTA,
+        REG_ALM_MOA,
+        REG_ALM_DWA,
+        REG_USR_USR1,
+        REG_USR_USR2
+    };
+
+    //Member constants
+    static const int m_ADDR = (0x6F << 1);
+
+    //Member variables
+    I2C m_I2C;
+
+    //Internal functions
+    char read8(char reg);
+    void write8(char reg, char data);
+    unsigned short read16(char reg);
+    void write16(char reg, unsigned short data);
+    unsigned int bcd2bin(unsigned char val);
+    char bin2bcd(unsigned int val);
+};
+
+#endif