LT_SPI

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Comitter:
roger5641
Date:
Sun Nov 12 01:21:36 2017 +0000
Commit message:
ver1

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LT_SPI.cpp Show annotated file Show diff for this revision Revisions of this file
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diff -r 000000000000 -r 516e11acba42 LT_SPI.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/LT_SPI.cpp	Sun Nov 12 01:21:36 2017 +0000
@@ -0,0 +1,310 @@
+//! @todo Review this document.
+/*!
+LT_SPI: Routines to communicate with ATmega328P's hardware SPI port.
+
+@verbatim
+
+LT_SPI implements the low level master SPI bus routines using
+the hardware SPI port.
+
+SPI Frequency = (CPU Clock frequency)/(16+2(TWBR)*Prescaler)
+SPCR = SPI Control Register (SPIE SPE DORD MSTR CPOL CPHA SPR1 SPR0)
+SPSR = SPI Status Register (SPIF WCOL - - - - - SPI2X)
+
+Data Modes:
+CPOL  CPHA  Leading Edge    Trailing Edge
+0      0    sample rising   setup falling
+0      1    setup rising    sample falling
+1      0    sample falling  setup rising
+1      1    sample rising   setup rising
+
+CPU Frequency = 16MHz on Arduino Uno
+SCK Frequency
+SPI2X  SPR1  SPR0  Frequency  Uno_Frequency
+  0      0     0     fosc/4     4 MHz
+  0      0     1     fosc/16    1 MHz
+  0      1     0     fosc/64    250 kHz
+  0      1     1     fosc/128   125 kHz
+  0      0     0     fosc/2     8 MHz
+  0      0     1     fosc/8     2 MHz
+  0      1     0     fosc/32    500 kHz
+
+@endverbatim
+
+REVISION HISTORY
+$Revision: 6237 $
+$Date: 2016-12-20 15:09:16 -0800 (Tue, 20 Dec 2016) $
+
+Copyright (c) 2013, Linear Technology Corp.(LTC)
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice, this
+   list of conditions and the following disclaimer.
+2. 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.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, 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.
+
+The views and conclusions contained in the software and documentation are those
+of the authors and should not be interpreted as representing official policies,
+either expressed or implied, of Linear Technology Corp.
+
+The Linear Technology Linduino is not affiliated with the official Arduino team.
+However, the Linduino is only possible because of the Arduino team's commitment
+to the open-source community.  Please, visit http://www.arduino.cc and
+http://store.arduino.cc , and consider a purchase that will help fund their
+ongoing work.
+*/
+
+//! @ingroup Linduino
+//! @{
+//! @defgroup LT_SPI LT_SPI: Routines to communicate with ATmega328P's hardware SPI port.
+//! @}
+
+/*! @file
+    @ingroup LT_SPI
+    Library for LT_SPI: Routines to communicate with ATmega328P's hardware SPI port.
+*/
+#include <stdint.h>
+#include "LT_SPI.h"
+
+//DigitalOut QUIKEVAL_GPIO D9;          //!< Linduino QuikEval GPIO pin (QuikEval connector pin 14) connects to Arduino pin 9
+//DigitalOut QUIKEVAL_CS A3;        //!< QuikEval CS pin (SPI chip select on QuikEval connector pin 6) connects to Arduino SS pin.
+//DigitalInOut QUIKEVAL_MUX_MODE_PIN(8,output);  /*!< QUIKEVAL_MUX_MODE_PIN defines the control pin for the QuikEval MUX.
+//The I2C port's SCL and the SPI port's SCK signals share the same pin on the Linduino's QuikEval connector.
+//Additionally, the I2C port's SDA and the SPI port's MOSI signals share the same pin on the Linduino's QuikEval connector.
+//The pair of pins connected to the QuikEval connector is switched using a MUX on the Linduino board.
+//The control pin to switch the MUX is defined as QUIKEVAL_MUX_MODE_PIN (Arduino pin 8). */
+
+void output_low(uint8_t pin)
+{
+    pin = 0;
+}
+void output_high(uint8_t pin)
+{
+    pin = 1;
+}
+
+
+// Reads and sends a byte
+// Return 0 if successful, 1 if failed
+void spi_transfer_byte(uint8_t cs_pin, uint8_t tx, uint8_t *rx)
+{
+  output_low(cs_pin);                 //! 1) Pull CS low
+
+  *rx = spi.write(tx);             //! 2) Read byte and send byte
+
+  output_high(cs_pin);                //! 3) Pull CS high
+}
+
+// Reads and sends a word
+// Return 0 if successful, 1 if failed
+void spi_transfer_word(uint8_t cs_pin, uint16_t tx, uint16_t *rx)
+{
+  union
+  {
+    uint8_t b[2];
+    uint16_t w;
+  } data_tx;
+
+  union
+  {
+    uint8_t b[2];
+    uint16_t w;
+  } data_rx;
+
+  data_tx.w = tx;
+
+  output_low(cs_pin);                         //! 1) Pull CS low
+
+  data_rx.b[1] = spi.write(data_tx.b[1]);  //! 2) Read MSB and send MSB
+  data_rx.b[0] = spi.write(data_tx.b[0]);  //! 3) Read LSB and send LSB
+
+  *rx = data_rx.w;
+
+  output_high(cs_pin);                        //! 4) Pull CS high
+}
+
+// Reads and sends a byte array
+void spi_transfer_block(uint8_t cs_pin, uint8_t *tx, uint8_t *rx, uint8_t length)
+{
+  int8_t i;
+
+  output_low(cs_pin);                 //! 1) Pull CS low
+
+  for (i=(length-1);  i >= 0; i--)
+    rx[i] = spi.write(tx[i]);    //! 2) Read and send byte array
+
+  output_high(cs_pin);                //! 3) Pull CS high
+}
+
+// Connect SPI pins to QuikEval connector through the Linduino MUX. This will disconnect I2C.
+//void quikeval_SPI_connect()
+//{
+//  output_high(QUIKEVAL_CS); //! 1) Pull Chip Select High
+//
+//  //! 2) Enable Main SPI
+//  pinMode(QUIKEVAL_MUX_MODE_PIN, OUTPUT);
+//  QUIKEVAL_MUX_MODE_PIN = 0;
+//}
+
+// Configure the SPI port for 4MHz SCK.
+// This function or spi_enable() must be called
+// before using the other SPI routines.
+//void quikeval_SPI_init(void)  // Initializes SPI
+//{
+//  spi_enable(SPI_CLOCK_DIV16);  //! 1) Configure the spi port for 4MHz SCK
+//}
+
+// Setup the processor for hardware SPI communication.
+// Must be called before using the other SPI routines.
+// Alternatively, call quikeval_SPI_connect(), which automatically
+// calls this function.
+void spi_enable(void) // Configures SCK frequency. Use constant defined in header file.
+{
+  //pinMode(SCK, OUTPUT);             //! 1) Setup SCK as output
+  //pinMode(MOSI, OUTPUT);            //! 2) Setup MOSI as output
+  //pinMode(QUIKEVAL_CS, OUTPUT);     //! 3) Setup CS as output
+  spi.format(16,3);
+  spi.frequency(1000000);
+}
+
+// Disable the SPI hardware port
+//void spi_disable()
+//{
+//  spi.end();
+//}
+
+// Write a data byte using the SPI hardware
+//void spi_write(int8_t  data)  // Byte to be written to SPI port
+//{
+//  SPDR = data;                  //! 1) Start the SPI transfer
+//  while (!(SPSR & _BV(SPIF)));  //! 2) Wait until transfer complete
+//}
+
+// Read and write a data byte using the SPI hardware
+// Returns the data byte read
+//int8_t spi_read(int8_t  data) //!The data byte to be written
+//{
+//  SPDR = data;                  //! 1) Start the SPI transfer
+//  while (!(SPSR & _BV(SPIF)));  //! 2) Wait until transfer complete
+//  return SPDR;                  //! 3) Return the data read
+//}
+
+// Below are implementations of spi_read, etc. that do not use the
+// Arduino SPI library.  To use these functions, uncomment them and comment out
+// the correcsponding function above.
+//
+// // Reads and sends a byte
+// // Return 0 if successful, 1 if failed
+// uint8_t spi_transfer_byte(uint8_t cs_pin, uint8_t tx, uint8_t *rx)
+// {
+//     output_low(cs_pin);                 //! 1) Pull CS low
+//
+//     *rx = spi_read(tx);                 //! 2) Read byte and send byte
+//
+//     output_high(cs_pin);                //! 3) Pull CS high
+//
+//     return(0);
+// }
+//
+// // Reads and sends a word
+// // Return 0 if successful, 1 if failed
+// uint8_t spi_transfer_word(uint8_t cs_pin, uint16_t tx, uint16_t *rx)
+// {
+//     union
+//     {
+//         uint8_t b[2];
+//         uint16_t w;
+//     } data_tx;
+//
+//     union
+//     {
+//         uint8_t b[2];
+//         uint16_t w;
+//     } data_rx;
+//
+//     data_tx.w = tx;
+//
+//     output_low(cs_pin);                     //! 1) Pull CS low
+//
+//     data_rx.b[1] = spi_read(data_tx.b[1]);  //! 2) Read MSB and send MSB
+//     data_rx.b[0] = spi_read(data_tx.b[0]);  //! 3) Read LSB and send LSB
+//     *rx = data_rx.w;
+//
+//     output_high(cs_pin);                    //! 4) Pull CS high
+//
+//     return(0);
+// }
+//
+// // Reads and sends a byte array
+// // Return 0 if successful, 1 if failed
+// uint8_t spi_transfer_block(uint8_t cs_pin, uint8_t *tx, uint8_t *rx, uint8_t length)
+// {
+//     int8_t i;
+//
+//     output_low(cs_pin);                 //! 1) Pull CS low
+//
+//     for(i=0;  i < length; i++)
+//         rx[i] = spi_read(tx[i]);        //! 2) Read and send byte array
+//
+//     output_high(cs_pin);                //! 3) Pull CS high
+//
+//     return(0);
+// }
+//
+// // Connect SPI pins to QuikEval connector through the Linduino MUX. This will disconnect I2C.
+// void quikeval_SPI_connect()
+// {
+//   output_high(QUIKEVAL_CS); //! 1) Pull Chip Select High
+//
+//   //! 2) Enable Main SPI
+//   pinMode(QUIKEVAL_MUX_MODE_PIN, OUTPUT);
+//   digitalWrite(QUIKEVAL_MUX_MODE_PIN, LOW);
+// }
+//
+// // Configure the SPI port for 4MHz SCK.
+// // This function or spi_enable() must be called
+// // before using the other SPI routines.
+// void quikeval_SPI_init(void)  // Initializes SPI
+// {
+//   spi_enable(SPI_CLOCK_DIV32);  //! 2) Configure the spi port for 4MHz SCK
+// }
+//
+// // Setup the processor for hardware SPI communication.
+// // Must be called before using the other SPI routines.
+// // Alternatively, call quikeval_SPI_connect(), which automatically
+// // calls this function.
+// void spi_enable(uint8_t spi_clock_divider) // Configures SCK frequency. Use constant defined in header file.
+// {
+//   pinMode(SCK, OUTPUT);             //! 1) Setup SCK as output
+//   pinMode(MOSI, OUTPUT);            //! 2) Setup MOSI as output
+//   pinMode(QUIKEVAL_CS, OUTPUT);     //! 3) Setup CS as output
+//   output_low(SCK);
+//   output_low(MOSI);
+//   output_high(QUIKEVAL_CS);
+//   SPCR |= _BV(MSTR);                //! 4) Set the SPI port to master mode
+//   //! 5) Set the SPI hardware rate
+//   SPCR = (SPCR & ~SPI_CLOCK_MASK) | (spi_clock_divider & SPI_CLOCK_MASK);
+//   SPSR = (SPSR & ~SPI_2XCLOCK_MASK) | ((spi_clock_divider >> 2) & SPI_2XCLOCK_MASK);
+//   SPCR |= _BV(SPE);                 //! 5) Enable the SPI port
+// }
+//
+// // Disable the SPI hardware port
+// void spi_disable()
+// {
+//   SPCR &= ~_BV(SPE);
+// }
\ No newline at end of file
diff -r 000000000000 -r 516e11acba42 LT_SPI.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/LT_SPI.h	Sun Nov 12 01:21:36 2017 +0000
@@ -0,0 +1,131 @@
+//! @todo Review this document.
+/*!
+LT_SPI: Routines to communicate with ATmega328P's hardware SPI port.
+
+REVISION HISTORY
+$Revision: 3659 $
+$Date: 2015-07-01 10:19:20 -0700 (Wed, 01 Jul 2015) $
+
+Copyright (c) 2013, Linear Technology Corp.(LTC)
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice, this
+   list of conditions and the following disclaimer.
+2. 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.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, 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.
+
+The views and conclusions contained in the software and documentation are those
+of the authors and should not be interpreted as representing official policies,
+either expressed or implied, of Linear Technology Corp.
+
+The Linear Technology Linduino is not affiliated with the official Arduino team.
+However, the Linduino is only possible because of the Arduino team's commitment
+to the open-source community.  Please, visit http://www.arduino.cc and
+http://store.arduino.cc , and consider a purchase that will help fund their
+ongoing work.
+*/
+
+/*! @file
+    @ingroup LT_SPI
+    Library Header File for LT_SPI: Routines to communicate with ATmega328P's hardware SPI port.
+*/
+
+#ifndef LT_SPI_H
+#define LT_SPI_H
+
+#include "mbed.h"
+
+SPI spi(A6,A5,A4,A3);
+// Uncomment the following to use functions that implement LTC SPI routines
+
+// //! @name SPI CLOCK DIVIDER CONSTANTS
+// //! @{
+// #define SPI_CLOCK_DIV4    0x00  // 4 Mhz
+// #define SPI_CLOCK_DIV16   0x01  // 1 Mhz
+// #define SPI_CLOCK_DIV64   0x02  // 250 khz
+// #define SPI_CLOCK_DIV128  0x03  // 125 khz
+// #define SPI_CLOCK_DIV2    0x04  // 8 Mhz
+// #define SPI_CLOCK_DIV8    0x05  // 2 Mhz
+// #define SPI_CLOCK_DIV32   0x06  // 500 khz
+// //! @}
+//
+// //! @name SPI HARDWARE MODE CONSTANTS
+// //! @{
+// #define SPI_MODE0 0x00
+// #define SPI_MODE1 0x04
+// // #define SPI_MODE2 0x08
+// #define SPI_MODE3 0x0C
+// //! @}
+//
+// //! @name SPI SET MASKS
+//! @{
+// #define SPI_MODE_MASK      0x0C    // CPOL = bit 3, CPHA = bit 2 on SPCR
+// #define SPI_CLOCK_MASK     0x03    // SPR1 = bit 1, SPR0 = bit 0 on SPCR
+// #define SPI_2XCLOCK_MASK   0x01    // SPI2X = bit 0 on SPSR
+// //! @}
+
+//! Reads and sends a byte
+//! @return void
+void spi_transfer_byte(uint8_t cs_pin,      //!< Chip select pin
+                       uint8_t tx,          //!< Byte to be transmitted
+                       uint8_t *rx          //!< Byte to be received
+                      );
+
+//! Reads and sends a word
+//! @return void
+void spi_transfer_word(uint8_t cs_pin,      //!< Chip select pin
+                       uint16_t tx,         //!< Byte to be transmitted
+                       uint16_t *rx         //!< Byte to be received
+                      );
+
+//! Reads and sends a byte array
+//! @return void
+void spi_transfer_block(uint8_t cs_pin,     //!< Chip select pin
+                        uint8_t *tx,        //!< Byte array to be transmitted
+                        uint8_t *rx,        //!< Byte array to be received
+                        uint8_t length      //!< Length of array
+                       );
+
+//! Connect SPI pins to QuikEval connector through the Linduino MUX. This will disconnect I2C.
+//void quikeval_SPI_connect();
+
+//! Configure the SPI port for 4Mhz SCK.
+//! This function or spi_enable() must be called
+//! before using the other SPI routines.
+//void quikeval_SPI_init();
+
+//! Setup the processor for hardware SPI communication.
+//! Must be called before using the other SPI routines.
+//! Alternatively, call quikeval_SPI_connect(), which automatically
+//! calls this function.
+void spi_enable(void);   //!< Configures SCK frequency. Use constant defined in header file.
+               
+
+//! Disable the SPI hardware port
+//void spi_disable();
+
+//! Write a data byte using the SPI hardware
+//void spi_write(int8_t data  //!< Byte to be written to SPI port
+//              );
+
+//! Read and write a data byte using the SPI hardware
+//! @return the data byte read
+//int8_t spi_read(int8_t data //!< The data byte to be written
+//               );
+
+#endif  // LT_SPI_H
\ No newline at end of file