AD5270.h

00001 /**
00002 *   @file     AD5270.h
00003 *   @brief    Header file for AD5270 rheostat
00004 *   @author   Analog Devices Inc.
00005 *
00006 * For support please go to:
00007 * Github: https://github.com/analogdevicesinc/mbed-adi
00008 * Support: https://ez.analog.com/community/linux-device-drivers/microcontroller-no-os-drivers
00009 * Product: http://www.analog.com/ad5270
00010 * More: https://wiki.analog.com/resources/tools-software/mbed-drivers-all
00011 
00012 ********************************************************************************
00013 * Copyright 2016(c) Analog Devices, Inc.
00014 *
00015 * All rights reserved.
00016 *
00017 * Redistribution and use in source and binary forms, with or without
00018 * modification, are permitted provided that the following conditions are met:
00019 *  - Redistributions of source code must retain the above copyright
00020 *    notice, this list of conditions and the following disclaimer.
00021 *  - Redistributions in binary form must reproduce the above copyright
00022 *    notice, this list of conditions and the following disclaimer in
00023 *    the documentation and/or other materials provided with the
00024 *    distribution.
00025 *  - Neither the name of Analog Devices, Inc. nor the names of its
00026 *    contributors may be used to endorse or promote products derived
00027 *    from this software without specific prior written permission.
00028 *  - The use of this software may or may not infringe the patent rights
00029 *    of one or more patent holders.  This license does not release you
00030 *    from the requirement that you obtain separate licenses from these
00031 *    patent holders to use this software.
00032 *  - Use of the software either in source or binary form, must be run
00033 *    on or directly connected to an Analog Devices Inc. component.
00034 *
00035 * THIS SOFTWARE IS PROVIDED BY ANALOG DEVICES "AS IS" AND ANY EXPRESS OR
00036 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, NON-INFRINGEMENT,
00037 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
00038 * IN NO EVENT SHALL ANALOG DEVICES BE LIABLE FOR ANY DIRECT, INDIRECT,
00039 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
00040 * LIMITED TO, INTELLECTUAL PROPERTY RIGHTS, PROCUREMENT OF SUBSTITUTE GOODS OR
00041 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
00042 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
00043 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
00044 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
00045 *
00046 ********************************************************************************/
00047 
00048 #ifndef AD5270_H
00049 #define AD5270_H
00050 
00051 #include "mbed.h"
00052 
00053 /**
00054  * @brief Analog Devices AD5270 SPI Digital Rheostat class
00055  */
00056 class AD5270
00057 {
00058 public:
00059 
00060     /// AD5270 commands
00061     typedef enum {
00062         NO_OP               =  0x00,    ///< No data
00063         NO_OP_cmd           =  0x0000,  ///< 16 bit no data
00064         WRITE_RDAC          =  0x04,    ///< Write to the RDAC Register
00065         READ_RDAC           =  0x08,    ///< Read from the RDAC Register
00066         STORE_50TP          =  0x0C,    ///< Write from RDAC to memory
00067         SW_RST              =  0x10,    ///< Software reset to last memory location
00068         READ_50TP_CONTENTS  =  0x14,    ///< Read the last memory contents
00069         READ_50TP_ADDRESS   =  0x18,    ///< Read the last memory address
00070         WRITE_CTRL_REG      =  0x1C,    ///< Write to the control Register
00071         READ_CTRL_REG       =  0x20,    ///< Read from the control Register
00072         SW_SHUTDOWN         =  0x24,    ///< Software shutdown (0) - Normal, (1) - Shutdown
00073         HI_Zupper           =  0x80,    ///< Get the SDO line ready for High Z
00074         HI_Zlower           =  0x01,    ///< Puts AD5270 into High Z mode
00075         HI_Z_Cmd            =  0x8001   ///< Puts AD5270 into High Z mode*/
00076     } AD5270Commands_t;
00077 
00078     typedef enum {
00079         NORMAL_MODE = 0,
00080         SHUTDOWN_MODE = 1
00081     } AD5270Modes_t;
00082 
00083     typedef enum {
00084         PROGRAM_50TP_ENABLE = 1,
00085         RDAC_WRITE_PROTECT = 2,
00086         R_PERFORMANCE_ENABLE = 4,
00087         MEMORY_PROGRAM_SUCCESFUL = 8
00088     } AD5270ControlRegisterBits_t;
00089 
00090     // SPI configuration & constructor
00091     AD5270(PinName CS = SPI_CS, float max_resistance = 20000.0, PinName MOSI = SPI_MOSI, PinName MISO = SPI_MISO, PinName SCK = SPI_SCK);
00092     void frequency(int hz);
00093 
00094     /* RDAC commands */
00095     void write_ctrl_reg(uint8_t data);
00096     uint8_t read_ctrl_reg(void);
00097     void change_mode(AD5270Modes_t mode);
00098     void set_SDO_HiZ(void);
00099 
00100     /* Wiper R/W methods*/
00101     void reset_RDAC(void);
00102     void write_wiper_reg(uint16_t data);
00103     uint16_t read_wiper_reg(void);
00104 
00105 
00106     /* Low level methods */
00107     uint16_t write_cmd(uint8_t command, uint16_t data = 0x00, bool toggle_cs = true);
00108     uint16_t write_reg(uint16_t data, bool toggle_cs = true);
00109 
00110     /* Methods that deal with resistance in float format*/
00111     uint16_t calc_RDAC(float resistance);
00112     float write_RDAC(float resistance);
00113     float read_RDAC(void);
00114     float get_max_resistance(void);
00115 
00116     /* 50 TP methods */
00117     void enable_50TP_programming(void);
00118     void store_50TP(void);
00119     void disable_50TP_programming(void);
00120     uint8_t read_50TP_last_address(void);
00121     uint16_t read_50TP_memory(uint8_t address);
00122 
00123     void daisy_chain(uint8_t *buffer, uint8_t size);
00124 
00125     SPI ad5270;    ///< SPI instance of the AD5270
00126     DigitalOut cs; ///< DigitalOut instance for the chip select of the AD5270
00127 
00128 private:
00129     const static int _RESET = 0xff;
00130     const static int _REG_OPERATION_TIMEOUT = 2;
00131     const static int _MEMORY_OPERATION_TIMEOUT = 6;
00132     const static int _WRITE_OPERATION_50TP_TIMEOUT = 350;
00133     const static int _DUMMY_BYTE = 0xAA;
00134     const static uint8_t _SPI_MODE = 1;
00135     float _max_resistance;
00136 };
00137 
00138 #endif