Diff: AD7791.h

Revision:

0:075fe3d08488

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/AD7791.h	Tue May 03 12:57:07 2016 +0000
@@ -0,0 +1,176 @@
+/**
+*   @file     AD7791.h
+*   @brief    Header file for AD7791 ADC
+*   @author   Analog Devices Inc.
+*
+* For support please go to:
+* Github: https://github.com/analogdevicesinc/mbed-adi
+* Support: https://ez.analog.com/community/linux-device-drivers/microcontroller-no-os-drivers
+* Product: http://www.analog.com/ad7791
+* More: https://wiki.analog.com/resources/tools-software/mbed-drivers-all
+
+********************************************************************************
+* Copyright 2016(c) Analog Devices, Inc.
+*
+* All rights reserved.
+*
+* Redistribution and use in source and binary forms, with or without
+* modification, are permitted provided that the following conditions are met:
+*  - Redistributions of source code must retain the above copyright
+*    notice, this list of conditions and the following disclaimer.
+*  - Redistributions in binary form must reproduce the above copyright
+*    notice, this list of conditions and the following disclaimer in
+*    the documentation and/or other materials provided with the
+*    distribution.
+*  - Neither the name of Analog Devices, Inc. nor the names of its
+*    contributors may be used to endorse or promote products derived
+*    from this software without specific prior written permission.
+*  - The use of this software may or may not infringe the patent rights
+*    of one or more patent holders.  This license does not release you
+*    from the requirement that you obtain separate licenses from these
+*    patent holders to use this software.
+*  - Use of the software either in source or binary form, must be run
+*    on or directly connected to an Analog Devices Inc. component.
+*
+* THIS SOFTWARE IS PROVIDED BY ANALOG DEVICES "AS IS" AND ANY EXPRESS OR
+* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, NON-INFRINGEMENT,
+* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+* IN NO EVENT SHALL ANALOG DEVICES BE LIABLE FOR ANY DIRECT, INDIRECT,
+* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+* LIMITED TO, INTELLECTUAL PROPERTY RIGHTS, PROCUREMENT OF SUBSTITUTE GOODS OR
+* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*
+********************************************************************************/
+
+#ifndef AD7791_H
+#define AD7791_H
+
+#include "mbed.h"
+
+/**
+ * Comment this line if you want to turn off the debug mode.
+ * The debug mode will send a message if an exception occurs within AD7791 driver
+ */
+
+#define AD7791_DEBUG_MODE
+
+/**
+ * @brief Analog Devices AD7791 SPI 16-bit Buffered Sigma-Delta ADC
+ */
+class AD7791
+{
+public:
+    /// AD7791 registers
+    typedef enum {
+        COMMUNICATION_REG = 0, ///< Communication register
+        STATUS_REG = 0,        ///< Status register
+        MODE_REG,              ///< Mode register
+        FILTER_REG,            ///< Filter Register
+        DATA_REG               ///< Data register
+    } AD7791Register_t;
+
+    /// AD7791 channel configuration
+    typedef enum {
+        DIFFERENTIAL = 0, ///< AIN(+)-AIN(-)
+        RESERVED,     ///< reserved
+        SHORT,        ///< AIN(-)-AIN(-)
+        VDDMONITOR    ///< Monitor VDD
+    } AD7791Channel_t;
+
+    typedef enum {
+        CONTINOUS_CONVERSION_MODE = 0,
+        SINGLE_CONVERSION_MODE = 0x80,
+        SHUTDOWN_MODE = 0xC0
+    } AD7791Mode_t;
+
+    typedef enum    {
+        MD1 = 0x80, ///< Mode Select Bit 1
+        MD0 = 0x40, ///< Mode Select Bit 0
+//      G1 = 0x20,  ///< Range bit 1
+//      G0 = 0x10,  ///< Range bit 0
+        BO = 0x08,  ///< Burnout Current Enable bit
+        UB = 0x04,  ///< Unipolar/Bipolar bit
+        BUF = 0x02, ///< Buffered mode bit
+    } ModeRegisterBits_t;
+
+    typedef enum {
+        CLKDIV1 = 0x40, ///< Clock divider bit 1
+        CLKDIV0 = 0x20, ///< Clock divider bit 0
+        FS2 = 0x04, ///< Update rate bit 2
+        FS1 = 0x02, ///< Update rate bit 1
+        FS0 = 0x01, ///< Update rate bit 0
+    } FilterRegisterBits_t;
+
+    /*  typedef enum    {
+            RANGE_VREF = 0,
+            RANGE_VREF_DIV_2,
+            RANGE_VREF_DIV_4,
+            RANGE_VREF_DIV_8,
+        } AnalogInputRange_t;
+    */
+    /** SPI configuration & constructor */
+    AD7791( float reference_voltage, PinName CS = SPI_CS, PinName MOSI = SPI_MOSI, PinName MISO = SPI_MISO, PinName SCK = SPI_SCK);
+    void frequency(int hz);
+
+    /** Low level SPI bus comm methods */
+    void reset(void);
+
+    /** Register access methods*/
+    void set_channel(AD7791Channel_t channel);
+    void set_conversion_mode(AD7791Mode_t mode);
+    uint32_t read_data_reg();
+    uint8_t read_status_reg(void);
+    void write_filter_reg(uint8_t regVal);
+    uint8_t read_filter_reg(void);
+    void write_mode_reg(uint8_t regVal);
+    uint8_t read_mode_reg(void);
+//  void  set_range(AnalogInputRange_t range);
+//  AnalogInputRange_t get_range(void);
+
+    /** Reference voltage methods */
+    void  set_reference_voltage(float ref);
+    float get_reference_voltage(void);
+
+    /** Voltage read methods */
+    float read_voltage(void);
+    float data_to_voltage(uint32_t data);
+    uint32_t voltage_to_data(float voltage);
+
+    /** AnalogIn API */
+    float read(void);
+    uint32_t read_u32(void);
+    uint16_t read_u16(void);
+
+#ifdef MBED_OPERATORS
+    operator float();
+#endif
+
+private:
+    DigitalIn miso;
+    SPI ad7791;    ///< SPI instance of the AD7791
+    DigitalOut cs; ///< DigitalOut instance for the chipselect of the AD7791
+
+    float _vref;
+//  uint8_t _PGA_gain;
+    bool _continous_conversion;
+    AD7791Channel_t _channel;
+
+    void write_reg(AD7791Register_t regAddress, uint8_t regValue);
+    uint16_t write_spi(uint16_t data);
+    uint16_t read_reg (AD7791Register_t regAddress);
+
+    const static uint16_t _SINGLE_CONVERSION_TIMEOUT = 0xFFFF; // in 10us = 100ms
+    const static uint16_t _CONTINOUS_CONVERSION_TIMEOUT = 0xFFFF;
+    const static uint32_t _RESOLUTION = 0xFFFFFF;
+    const static uint8_t _RESET = 0xFF;
+    const static uint8_t _DUMMY_BYTE = 0xFF;
+    const static uint16_t _READ_FLAG = 0x0800;
+    const static uint8_t _DATA_READ    = 0x38;             // Read from the Data Register
+    const static uint8_t _DELAY_TIMING = 0x02;
+    const static uint8_t _SPI_MODE = 3;
+};
+
+#endif