LUFA/Drivers/Peripheral/AVR8/SerialSPI_AVR8.h

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2013.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6            www.lufa-lib.org
   7 */
   8
   9 /*
  10   Copyright 2013  Dean Camera (dean [at] fourwalledcubicle [dot] com)
  11
  12   Permission to use, copy, modify, distribute, and sell this
  13   software and its documentation for any purpose is hereby granted
  14   without fee, provided that the above copyright notice appear in
  15   all copies and that both that the copyright notice and this
  16   permission notice and warranty disclaimer appear in supporting
  17   documentation, and that the name of the author not be used in
  18   advertising or publicity pertaining to distribution of the
  19   software without specific, written prior permission.
  20
  21   The author disclaims all warranties with regard to this
  22   software, including all implied warranties of merchantability
  23   and fitness.  In no event shall the author be liable for any
  24   special, indirect or consequential damages or any damages
  25   whatsoever resulting from loss of use, data or profits, whether
  26   in an action of contract, negligence or other tortious action,
  27   arising out of or in connection with the use or performance of
  28   this software.
  29 */
  30
  31 /** \file
  32  *  \brief Master SPI Mode Serial USART Peripheral Driver (XMEGA)
  33  *
  34  *  On-chip Master SPI mode USART driver for the XMEGA AVR microcontrollers.
  35  *
  36  *  \note This file should not be included directly. It is automatically included as needed by the SPI Master
  37  *        Mode USART driver dispatch header located in LUFA/Drivers/Peripheral/Serial.h.
  38  */
  39
  40 /** \ingroup Group_SerialSPI
  41  *  \defgroup Group_SerialSPI_AVR8 Master SPI Mode Serial USART Peripheral Driver (AVR8)
  42  *
  43  *  \section Sec_SerialSPI_AVR8_ModDescription Module Description
  44  *  On-chip serial USART driver for the 8-bit AVR8 microcontrollers.
  45  *
  46  *  \note This file should not be included directly. It is automatically included as needed by the SPI Master
  47  *        driver dispatch header located in LUFA/Drivers/Peripheral/SerialSPI.h.
  48  *
  49  *  \section Sec_SerialSPI_AVR8_ExampleUsage Example Usage
  50  *  The following snippet is an example of how this module may be used within a typical
  51  *  application.
  52  *
  53  *  \code
  54  *      // Initialize the Master SPI mode USART driver before first use, with 1Mbit baud
  55  *      SerialSPI_Init((USART_SPI_SCK_LEAD_RISING | SPI_SAMPLE_LEADING | SPI_ORDER_MSB_FIRST), 1000000);
  56  *
  57  *      // Send several bytes, ignoring the returned data
  58  *      SerialSPI_SendByte(0x01);
  59  *      SerialSPI_SendByte(0x02);
  60  *      SerialSPI_SendByte(0x03);
  61  *
  62  *      // Receive several bytes, sending a dummy 0x00 byte each time
  63  *      uint8_t Byte1 = SerialSPI_ReceiveByte();
  64  *      uint8_t Byte2 = SerialSPI_ReceiveByte();
  65  *      uint8_t Byte3 = SerialSPI_ReceiveByte();
  66  *
  67  *      // Send a byte, and store the received byte from the same transaction
  68  *      uint8_t ResponseByte = SerialSPI_TransferByte(0xDC);
  69  *  \endcode
  70  *
  71  *  @{
  72  */
  73
  74 #ifndef __SERIAL_SPI_AVR8_H__
  75 #define __SERIAL_SPI_AVR8_H__
  76
  77         /* Includes: */
  78                 #include "../../../Common/Common.h"
  79
  80                 #include <stdio.h>
  81
  82         /* Enable C linkage for C++ Compilers: */
  83                 #if defined(__cplusplus)
  84                         extern "C" {
  85                 #endif
  86
  87         /* Preprocessor Checks: */
  88                 #if !defined(__INCLUDE_FROM_SERIAL_SPI_H)
  89                         #error Do not include this file directly. Include LUFA/Drivers/Peripheral/Serial.h instead.
  90                 #endif
  91
  92         /* Private Interface - For use in library only: */
  93         #if !defined(__DOXYGEN__)
  94                         #define SERIAL_SPI_UBBRVAL(Baud)       ((Baud < (F_CPU / 2)) ? ((F_CPU / (2 * Baud)) - 1) : 0)
  95         #endif
  96
  97         /* Public Interface - May be used in end-application: */
  98                 /* Macros: */
  99                         /** \name SPI SCK Polarity Configuration Masks */
 100                         //@{
 101                         /** SPI clock polarity mask for \ref SPI_Init(). Indicates that the SCK should lead on the rising edge. */
 102                         #define USART_SPI_SCK_LEAD_RISING            (0 << UCPOL)
 103
 104                         /** SPI clock polarity mask for \ref SPI_Init(). Indicates that the SCK should lead on the falling edge. */
 105                         #define USART_SPI_SCK_LEAD_FALLING           (1 << UCPOL)
 106                         //@}
 107
 108                         /** \name SPI Sample Edge Configuration Masks */
 109                         //@{
 110                         /** SPI data sample mode mask for \ref SerialSPI_Init(). Indicates that the data should sampled on the leading edge. */
 111                         #define USART_SPI_SAMPLE_LEADING             (0 << UPCHA)
 112
 113                         /** SPI data sample mode mask for \ref SerialSPI_Init(). Indicates that the data should be sampled on the trailing edge. */
 114                         #define USART_SPI_SAMPLE_TRAILING            (1 << UPCHA)
 115                         //@}
 116
 117                         /** \name SPI Data Ordering Configuration Masks */
 118                         //@{
 119                         /** SPI data order mask for \ref SerialSPI_Init(). Indicates that data should be shifted out MSB first. */
 120                         #define USART_SPI_ORDER_MSB_FIRST            (0 << UDORD)
 121
 122                         /** SPI data order mask for \ref SerialSPI_Init(). Indicates that data should be shifted out LSB first. */
 123                         #define USART_SPI_ORDER_LSB_FIRST            (1 << UDORD)
 124                         //@}
 125
 126                 /* Inline Functions: */
 127                         /** Initialize the USART module in Master SPI mode.
 128                          *
 129                          *  \param[in]     SPIOptions   USART SPI Options, a mask consisting of one of each of the \c USART_SPI_SCK_*,
 130                          *                              \c USART_SPI_SAMPLE_* and \c USART_SPI_ORDER_* masks.
 131                          *  \param[in]     BaudRate     SPI baud rate, in bits per second.
 132                          */
 133                         static inline void SerialSPI_Init(const uint8_t SPIOptions,
 134                                                           const uint32_t BaudRate)
 135                         {
 136                                 DDRD  |= ((1 << 3) | (1 << 5));
 137                                 PORTD |= (1 << 2);
 138
 139                                 UCSR1C = ((1 << UMSEL11) | (1 << UMSEL10) | SPIOptions);
 140                                 UCSR1B = ((1 << TXEN1)  | (1 << RXEN1));
 141
 142                                 UBRR1  = SERIAL_SPI_UBBRVAL(BaudRate);
 143                         }
 144
 145                         /** Turns off the USART driver, disabling and returning used hardware to their default configuration. */
 146                         static inline void SerialSPI_Disable(void)
 147                         {
 148                                 UCSR1B = 0;
 149                                 UCSR1A = 0;
 150                                 UCSR1C = 0;
 151
 152                                 UBRR1  = 0;
 153
 154                                 DDRD  &= ~((1 << 3) | (1 << 5));
 155                                 PORTD &= ~(1 << 2);
 156                         }
 157
 158                         /** Sends and receives a byte through the USART SPI interface, blocking until the transfer is complete.
 159                          *
 160                          *  \param[in] DataByte  Byte to send through the USART SPI interface.
 161                          *
 162                          *  \return Response byte from the attached SPI device.
 163                          */
 164                         static inline uint8_t SerialSPI_TransferByte(const uint8_t DataByte)
 165                         {
 166                                 UDR1 = DataByte;
 167                                 while (!(UCSR1A & (1 << TXC1)));
 168                                 UCSR1A = (1 << TXC1);
 169                                 return UDR1;
 170                         }
 171
 172                         /** Sends a byte through the USART SPI interface, blocking until the transfer is complete. The response
 173                          *  byte sent to from the attached SPI device is ignored.
 174                          *
 175                          *  \param[in] DataByte  Byte to send through the USART SPI interface.
 176                          */
 177                         static inline void SerialSPI_SendByte(const uint8_t DataByte)
 178                         {
 179                                 SerialSPI_TransferByte(DataByte);
 180                         }
 181
 182                         /** Sends a dummy byte through the USART SPI interface, blocking until the transfer is complete. The response
 183                          *  byte from the attached SPI device is returned.
 184                          *
 185                          *  \return The response byte from the attached SPI device.
 186                          */
 187                         static inline uint8_t SerialSPI_ReceiveByte(void)
 188                         {
 189                                 return SerialSPI_TransferByte(0);
 190                         }
 191
 192         /* Disable C linkage for C++ Compilers: */
 193                 #if defined(__cplusplus)
 194                         }
 195                 #endif
 196
 197 #endif
 198
 199 /** @} */
 200