Analog Devices / mbed-drivers

A collection of Analog Devices drivers for the mbed platform

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

libraries/ad5270/AD5270.cpp@3:1a8c14043a4e, 2016-04-01 (annotated)

Committer:
Suciu
Date:
Fri Apr 01 10:53:41 2016 +0300
Revision:
3:1a8c14043a4e
Parent:
1:c1f0670bb370
Child:
4:5c1b28aff7e1
Added license, file headers and fixed missing whitespaces

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Suciu 1:c1f0670bb370 1 /**
Suciu 1:c1f0670bb370 2 * @file AD5270.cpp
Suciu 1:c1f0670bb370 3 * @brief Source file for AD5270 rheostat
Suciu 3:1a8c14043a4e 4 * @author Analog Devices Inc.
Suciu 3:1a8c14043a4e 5 *
Suciu 3:1a8c14043a4e 6 * For support please go to:
Suciu 3:1a8c14043a4e 7 * Github: https://github.com/analogdevicesinc/mbed-adi
Suciu 3:1a8c14043a4e 8 * Support: https://ez.analog.com/community/linux-device-drivers/microcontroller-no-os-drivers
Suciu 3:1a8c14043a4e 9 * Product: http://www.analog.com/ad5270
Suciu 3:1a8c14043a4e 10 * More: https://wiki.analog.com/resources/tools-software/mbed-drivers-all
Suciu 3:1a8c14043a4e 11
Suciu 3:1a8c14043a4e 12 ********************************************************************************
Suciu 3:1a8c14043a4e 13 * Copyright 2016(c) Analog Devices, Inc.
Suciu 3:1a8c14043a4e 14 *
Suciu 3:1a8c14043a4e 15 * All rights reserved.
Suciu 3:1a8c14043a4e 16 *
Suciu 3:1a8c14043a4e 17 * Redistribution and use in source and binary forms, with or without
Suciu 3:1a8c14043a4e 18 * modification, are permitted provided that the following conditions are met:
Suciu 3:1a8c14043a4e 19 * - Redistributions of source code must retain the above copyright
Suciu 3:1a8c14043a4e 20 * notice, this list of conditions and the following disclaimer.
Suciu 3:1a8c14043a4e 21 * - Redistributions in binary form must reproduce the above copyright
Suciu 3:1a8c14043a4e 22 * notice, this list of conditions and the following disclaimer in
Suciu 3:1a8c14043a4e 23 * the documentation and/or other materials provided with the
Suciu 3:1a8c14043a4e 24 * distribution.
Suciu 3:1a8c14043a4e 25 * - Neither the name of Analog Devices, Inc. nor the names of its
Suciu 3:1a8c14043a4e 26 * contributors may be used to endorse or promote products derived
Suciu 3:1a8c14043a4e 27 * from this software without specific prior written permission.
Suciu 3:1a8c14043a4e 28 * - The use of this software may or may not infringe the patent rights
Suciu 3:1a8c14043a4e 29 * of one or more patent holders. This license does not release you
Suciu 3:1a8c14043a4e 30 * from the requirement that you obtain separate licenses from these
Suciu 3:1a8c14043a4e 31 * patent holders to use this software.
Suciu 3:1a8c14043a4e 32 * - Use of the software either in source or binary form, must be run
Suciu 3:1a8c14043a4e 33 * on or directly connected to an Analog Devices Inc. component.
Suciu 3:1a8c14043a4e 34 *
Suciu 3:1a8c14043a4e 35 * THIS SOFTWARE IS PROVIDED BY ANALOG DEVICES "AS IS" AND ANY EXPRESS OR
Suciu 3:1a8c14043a4e 36 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, NON-INFRINGEMENT,
Suciu 3:1a8c14043a4e 37 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
Suciu 3:1a8c14043a4e 38 * IN NO EVENT SHALL ANALOG DEVICES BE LIABLE FOR ANY DIRECT, INDIRECT,
Suciu 3:1a8c14043a4e 39 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
Suciu 3:1a8c14043a4e 40 * LIMITED TO, INTELLECTUAL PROPERTY RIGHTS, PROCUREMENT OF SUBSTITUTE GOODS OR
Suciu 3:1a8c14043a4e 41 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
Suciu 3:1a8c14043a4e 42 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
Suciu 3:1a8c14043a4e 43 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
Suciu 3:1a8c14043a4e 44 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
Suciu 3:1a8c14043a4e 45 *
Suciu 3:1a8c14043a4e 46 ********************************************************************************/
Suciu 3:1a8c14043a4e 47
Suciu 1:c1f0670bb370 48
Suciu 1:c1f0670bb370 49 #include "mbed.h"
Suciu 1:c1f0670bb370 50 #include "AD5270.h"
Suciu 1:c1f0670bb370 51
Suciu 1:c1f0670bb370 52 /**
Suciu 1:c1f0670bb370 53 * @brief AD5270 constructor, sets CS pin and SPI format
Suciu 1:c1f0670bb370 54 * @param CS - (optional)chip select of the AD5270
Suciu 1:c1f0670bb370 55 * @param max_resistance - (optional) nominal resistance of the AD5270 chip in ohms
Suciu 1:c1f0670bb370 56 * @param MOSI - (optional)pin of the SPI interface
Suciu 1:c1f0670bb370 57 * @param MISO - (optional)pin of the SPI interface
Suciu 1:c1f0670bb370 58 * @param SCK - (optional)pin of the SPI interface
Suciu 1:c1f0670bb370 59 */
Suciu 3:1a8c14043a4e 60 AD5270::AD5270(PinName CS, float max_resistance, PinName MOSI, PinName MISO, PinName SCK):
Suciu 3:1a8c14043a4e 61 ad5270(MOSI, MISO, SCK), cs(CS), _max_resistance(max_resistance)
Suciu 1:c1f0670bb370 62 {
Suciu 3:1a8c14043a4e 63 ad5270.format(8, 3);
Suciu 3:1a8c14043a4e 64 cs = true;
Suciu 1:c1f0670bb370 65 }
Suciu 1:c1f0670bb370 66
Suciu 1:c1f0670bb370 67 /**
Suciu 1:c1f0670bb370 68 * @brief Compute for the nearest RDAC value from given resistance
Suciu 1:c1f0670bb370 69 * @param resistance - resistor
Suciu 1:c1f0670bb370 70 * @return RDAC value - closest possible to given resistance
Suciu 1:c1f0670bb370 71 */
Suciu 1:c1f0670bb370 72 uint16_t AD5270::calc_RDAC(float resistance)
Suciu 1:c1f0670bb370 73 {
Suciu 1:c1f0670bb370 74 return static_cast<uint16_t>( (resistance / _max_resistance) * 1024.0 );
Suciu 1:c1f0670bb370 75 }
Suciu 1:c1f0670bb370 76
Suciu 1:c1f0670bb370 77 /**
Suciu 1:c1f0670bb370 78 * @brief Puts the AD5270 SDO line in to Hi-Z mode
Suciu 1:c1f0670bb370 79 * @return none
Suciu 1:c1f0670bb370 80 */
Suciu 1:c1f0670bb370 81 void AD5270::set_SDO_HiZ(void)
Suciu 1:c1f0670bb370 82 {
Suciu 1:c1f0670bb370 83 write_reg(HI_Z_Cmd);
Suciu 1:c1f0670bb370 84 write_reg(NO_OP_cmd);
Suciu 1:c1f0670bb370 85 }
Suciu 1:c1f0670bb370 86
Suciu 1:c1f0670bb370 87 /**
Suciu 1:c1f0670bb370 88 * @brief Set AD5270 SPI frequency
Suciu 1:c1f0670bb370 89 * @param hz - SPI bus frequency in hz
Suciu 1:c1f0670bb370 90 * @return none
Suciu 1:c1f0670bb370 91 */
Suciu 1:c1f0670bb370 92 void AD5270::frequency(int hz)
Suciu 1:c1f0670bb370 93 {
Suciu 1:c1f0670bb370 94 ad5270.frequency(hz);
Suciu 1:c1f0670bb370 95 }
Suciu 1:c1f0670bb370 96
Suciu 1:c1f0670bb370 97 /**
Suciu 1:c1f0670bb370 98 * @brief Issues AD5270 a command
Suciu 1:c1f0670bb370 99 * @param command - command to be sent
Suciu 1:c1f0670bb370 100 * @param data - (optional)value for the requested command
Suciu 1:c1f0670bb370 101 * @return response form the AD5270
Suciu 1:c1f0670bb370 102 */
Suciu 1:c1f0670bb370 103 uint16_t AD5270::write_cmd(uint8_t command, uint16_t data)
Suciu 1:c1f0670bb370 104 {
Suciu 1:c1f0670bb370 105 /* build 16 bit data to be written - Command + Value */
Suciu 1:c1f0670bb370 106 uint16_t ui16Command = ((command & 0x3C) << 8) | (data & 0x3FF);
Suciu 1:c1f0670bb370 107 return write_reg(ui16Command);
Suciu 1:c1f0670bb370 108 }
Suciu 1:c1f0670bb370 109
Suciu 1:c1f0670bb370 110 /**
Suciu 1:c1f0670bb370 111 * @brief Writes 16bit data to the AD5270 SPI interface
Suciu 1:c1f0670bb370 112 * @param data to be written
Suciu 1:c1f0670bb370 113 * @return data returned by the AD5270
Suciu 1:c1f0670bb370 114 */
Suciu 1:c1f0670bb370 115 uint16_t AD5270::write_reg(uint16_t data)
Suciu 1:c1f0670bb370 116 {
Suciu 1:c1f0670bb370 117 uint16_t result;
Suciu 1:c1f0670bb370 118 uint8_t upper_byte = (data >> 8) & 0xFF;
Suciu 1:c1f0670bb370 119 uint8_t lower_byte = data & 0xFF;
Suciu 1:c1f0670bb370 120 cs = false;
Suciu 1:c1f0670bb370 121 result = ((ad5270.write(upper_byte)) << 8);
Suciu 1:c1f0670bb370 122 result |= ad5270.write(lower_byte);
Suciu 1:c1f0670bb370 123 cs = true;
Suciu 1:c1f0670bb370 124 return result;
Suciu 1:c1f0670bb370 125 }
Suciu 1:c1f0670bb370 126
Suciu 1:c1f0670bb370 127 /**
Suciu 1:c1f0670bb370 128 * @brief Gets maximum resistance of the AD5270 digital rheostat
Suciu 1:c1f0670bb370 129 * @return maximum resistance in ohms
Suciu 1:c1f0670bb370 130 */
Suciu 1:c1f0670bb370 131 float AD5270::get_max_resistance()
Suciu 1:c1f0670bb370 132 {
Suciu 1:c1f0670bb370 133 return _max_resistance;
Suciu 1:c1f0670bb370 134 }