LT_SPI.h

00001 //! @todo Review this document.
00002 /*!
00003 LT_SPI: Routines to communicate with ATmega328P's hardware SPI port.
00004 
00005 REVISION HISTORY
00006 $Revision: 3659 $
00007 $Date: 2015-07-01 10:19:20 -0700 (Wed, 01 Jul 2015) $
00008 
00009 Copyright (c) 2013, Linear Technology Corp.(LTC)
00010 All rights reserved.
00011 
00012 Redistribution and use in source and binary forms, with or without
00013 modification, are permitted provided that the following conditions are met:
00014 
00015 1. Redistributions of source code must retain the above copyright notice, this
00016    list of conditions and the following disclaimer.
00017 2. Redistributions in binary form must reproduce the above copyright notice,
00018    this list of conditions and the following disclaimer in the documentation
00019    and/or other materials provided with the distribution.
00020 
00021 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
00022 ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
00023 WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
00024 DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
00025 ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
00026 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
00027 LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
00028 ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
00029 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
00030 SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
00031 
00032 The views and conclusions contained in the software and documentation are those
00033 of the authors and should not be interpreted as representing official policies,
00034 either expressed or implied, of Linear Technology Corp.
00035 
00036 The Linear Technology Linduino is not affiliated with the official Arduino team.
00037 However, the Linduino is only possible because of the Arduino team's commitment
00038 to the open-source community.  Please, visit http://www.arduino.cc and
00039 http://store.arduino.cc , and consider a purchase that will help fund their
00040 ongoing work.
00041 */
00042 
00043 /*! @file
00044     @ingroup LT_SPI
00045     Library Header File for LT_SPI: Routines to communicate with ATmega328P's hardware SPI port.
00046 */
00047 
00048 #ifndef LT_SPI_H
00049 #define LT_SPI_H
00050 
00051 #include "mbed.h"
00052 
00053 SPI spi(A6,A5,A4,A3);
00054 // Uncomment the following to use functions that implement LTC SPI routines
00055 
00056 // //! @name SPI CLOCK DIVIDER CONSTANTS
00057 // //! @{
00058 // #define SPI_CLOCK_DIV4    0x00  // 4 Mhz
00059 // #define SPI_CLOCK_DIV16   0x01  // 1 Mhz
00060 // #define SPI_CLOCK_DIV64   0x02  // 250 khz
00061 // #define SPI_CLOCK_DIV128  0x03  // 125 khz
00062 // #define SPI_CLOCK_DIV2    0x04  // 8 Mhz
00063 // #define SPI_CLOCK_DIV8    0x05  // 2 Mhz
00064 // #define SPI_CLOCK_DIV32   0x06  // 500 khz
00065 // //! @}
00066 //
00067 // //! @name SPI HARDWARE MODE CONSTANTS
00068 // //! @{
00069 // #define SPI_MODE0 0x00
00070 // #define SPI_MODE1 0x04
00071 // // #define SPI_MODE2 0x08
00072 // #define SPI_MODE3 0x0C
00073 // //! @}
00074 //
00075 // //! @name SPI SET MASKS
00076 //! @{
00077 // #define SPI_MODE_MASK      0x0C    // CPOL = bit 3, CPHA = bit 2 on SPCR
00078 // #define SPI_CLOCK_MASK     0x03    // SPR1 = bit 1, SPR0 = bit 0 on SPCR
00079 // #define SPI_2XCLOCK_MASK   0x01    // SPI2X = bit 0 on SPSR
00080 // //! @}
00081 
00082 //! Reads and sends a byte
00083 //! @return void
00084 void spi_transfer_byte(uint8_t cs_pin,      //!< Chip select pin
00085                        uint8_t tx,          //!< Byte to be transmitted
00086                        uint8_t *rx          //!< Byte to be received
00087                       );
00088 
00089 //! Reads and sends a word
00090 //! @return void
00091 void spi_transfer_word(uint8_t cs_pin,      //!< Chip select pin
00092                        uint16_t tx,         //!< Byte to be transmitted
00093                        uint16_t *rx         //!< Byte to be received
00094                       );
00095 
00096 //! Reads and sends a byte array
00097 //! @return void
00098 void spi_transfer_block(uint8_t cs_pin,     //!< Chip select pin
00099                         uint8_t *tx,        //!< Byte array to be transmitted
00100                         uint8_t *rx,        //!< Byte array to be received
00101                         uint8_t length      //!< Length of array
00102                        );
00103 
00104 //! Connect SPI pins to QuikEval connector through the Linduino MUX. This will disconnect I2C.
00105 //void quikeval_SPI_connect();
00106 
00107 //! Configure the SPI port for 4Mhz SCK.
00108 //! This function or spi_enable() must be called
00109 //! before using the other SPI routines.
00110 //void quikeval_SPI_init();
00111 
00112 //! Setup the processor for hardware SPI communication.
00113 //! Must be called before using the other SPI routines.
00114 //! Alternatively, call quikeval_SPI_connect(), which automatically
00115 //! calls this function.
00116 void spi_enable(void);   //!< Configures SCK frequency. Use constant defined in header file.
00117                
00118 
00119 //! Disable the SPI hardware port
00120 //void spi_disable();
00121 
00122 //! Write a data byte using the SPI hardware
00123 //void spi_write(int8_t data  //!< Byte to be written to SPI port
00124 //              );
00125 
00126 //! Read and write a data byte using the SPI hardware
00127 //! @return the data byte read
00128 //int8_t spi_read(int8_t data //!< The data byte to be written
00129 //               );
00130 
00131 #endif  // LT_SPI_H