Driver for the AD5270 digipot

Dependents:   ad5270-helloworld CN0357 CN0396

For additional information check out the mbed page of the Analog Devices wiki: https://wiki.analog.com/resources/tools-software/mbed-drivers-all

Revision:
0:18d434f6f122
Child:
1:9f9dd8c48e8a
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/AD5270.h	Tue May 03 12:55:30 2016 +0000
@@ -0,0 +1,136 @@
+/**
+*   @file     AD5270.h
+*   @brief    Header file for AD5270 rheostat
+*   @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/ad5270
+* 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 AD5270_H
+#define AD5270_H
+
+#include "mbed.h"
+
+/**
+ * @brief Analog Devices AD5270 SPI Digital Rheostat class
+ */
+class AD5270
+{
+public:
+
+    /// AD5270 commands
+    typedef enum {
+        NO_OP               =  0x00,    ///< No data
+        NO_OP_cmd           =  0x0000,  ///< 16 bit no data
+        WRITE_RDAC          =  0x04,    ///< Write to the RDAC Register
+        READ_RDAC           =  0x08,    ///< Read from the RDAC Register
+        STORE_50TP          =  0x0C,    ///< Write from RDAC to memory
+        SW_RST              =  0x10,    ///< Software reset to last memory location
+        READ_50TP_CONTENTS  =  0x14,    ///< Read the last memory contents
+        READ_50TP_ADDRESS   =  0x18,    ///< Read the last memory address
+        WRITE_CTRL_REG      =  0x1C,    ///< Write to the control Register
+        READ_CTRL_REG       =  0x20,    ///< Read from the control Register
+        SW_SHUTDOWN         =  0x24,    ///< Software shutdown (0) - Normal, (1) - Shutdown
+        HI_Zupper           =  0x80,    ///< Get the SDO line ready for High Z
+        HI_Zlower           =  0x01,    ///< Puts AD5270 into High Z mode
+        HI_Z_Cmd            =  0x8001   ///< Puts AD5270 into High Z mode*/
+    } AD5270Commands_t;
+
+    typedef enum {
+        NORMAL_MODE = 0,
+        SHUTDOWN_MODE = 1
+    } AD5270Modes_t;
+
+    typedef enum {
+        PROGRAM_50TP_ENABLE = 1,
+        RDAC_WRITE_PROTECT = 2,
+        R_PERFORMANCE_ENABLE = 4,
+        MEMORY_PROGRAM_SUCCESFUL = 8
+    } AD5270ControlRegisterBits_t;
+
+    // SPI configuration & constructor
+    AD5270(PinName CS = SPI_CS, float max_resistance = 20000.0, PinName MOSI = SPI_MOSI, PinName MISO = SPI_MISO, PinName SCK = SPI_SCK);
+    void frequency(int hz);
+
+    /* RDAC commands */
+    void write_ctrl_reg(uint8_t data);
+    uint8_t read_ctrl_reg(void);
+    void change_mode(AD5270Modes_t mode);
+    void set_SDO_HiZ(void);
+
+    /* Wiper R/W methods*/
+    void reset_RDAC(void);
+    void write_wiper_reg(uint16_t data);
+    uint16_t read_wiper_reg(void);
+
+
+    /* Low level methods */
+    uint16_t write_cmd(uint8_t command, uint16_t data = 0x00);
+    uint16_t write_reg(uint16_t data);
+
+    /* Methods that deal with resistance in float format*/
+    uint16_t calc_RDAC(float resistance);
+    float write_RDAC(float resistance);
+    float read_RDAC(void);
+    float get_max_resistance(void);
+
+    /* 50 TP methods */
+    void enable_50TP_programming(void);
+    void store_50TP(void);
+    void disable_50TP_programming(void);
+    uint8_t read_50TP_last_address(void);
+    uint16_t read_50TP_memory(uint8_t address);
+
+    SPI ad5270;    ///< SPI instance of the AD5270
+    DigitalOut cs; ///< DigitalOut instance for the chip select of the AD5270
+
+private:
+    const static int _RESET = 0xff;
+    const static int _REG_OPERATION_TIMEOUT = 2;
+    const static int _MEMORY_OPERATION_TIMEOUT = 6;
+    const static int _WRITE_OPERATION_50TP_TIMEOUT = 350;
+    const static int _DUMMY_BYTE = 0xAA;
+    const static uint8_t _SPI_MODE = 1;
+    float _max_resistance;
+};
+
+#endif