LUFA/Drivers/Peripheral/Serial.h

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2010.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6       www.fourwalledcubicle.com
   7 */
   8
   9 /*
  10   Copyright 2010  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 disclaim 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 include file for the USART peripheral driver.
  33  *
  34  *  Driver for the USART subsystem on supported USB AVRs.
  35  */
  36
  37 /** \ingroup Group_PeripheralDrivers
  38  *  @defgroup Group_Serial Serial USART Driver - LUFA/Drivers/Peripheral/Serial.h
  39  *
  40  *  \section Sec_Dependencies Module Source Dependencies
  41  *  The following files must be built with any user project that uses this module:
  42  *    - LUFA/Drivers/Peripheral/Serial.c
  43  *
  44  *  \section Module Description
  45  *  Hardware serial USART driver. This module provides an easy to use driver for
  46  *  the setup of and transfer of data over the AVR's USART port.
  47  *
  48  *  @{
  49  */
  50
  51 #ifndef __SERIAL_H__
  52 #define __SERIAL_H__
  53
  54         /* Includes: */
  55                 #include <avr/io.h>
  56                 #include <avr/pgmspace.h>
  57                 #include <stdbool.h>
  58
  59                 #include "../../Common/Common.h"
  60                 #include "../Misc/TerminalCodes.h"
  61
  62         /* Enable C linkage for C++ Compilers: */
  63                 #if defined(__cplusplus)
  64                         extern "C" {
  65                 #endif
  66
  67         /* Public Interface - May be used in end-application: */
  68                 /* Macros: */
  69                         /** Macro for calculating the baud value from a given baud rate when the U2X (double speed) bit is
  70                          *  not set.
  71                          */
  72                         #define SERIAL_UBBRVAL(baud)    ((((F_CPU / 16) + (baud / 2)) / (baud)) - 1)
  73
  74                         /** Macro for calculating the baud value from a given baud rate when the U2X (double speed) bit is
  75                          *  set.
  76                          */
  77                         #define SERIAL_2X_UBBRVAL(baud) ((((F_CPU / 8) + (baud / 2)) / (baud)) - 1)
  78
  79                 /* Pseudo-Function Macros: */
  80                         #if defined(__DOXYGEN__)
  81                                 /** Indicates whether a character has been received through the USART.
  82                                  *
  83                                  *  \return Boolean true if a character has been received, false otherwise.
  84                                  */
  85                                 static inline bool Serial_IsCharReceived(void);
  86                         #else
  87                                 #define Serial_IsCharReceived() ((UCSR1A & (1 << RXC1)) ? true : false)
  88                         #endif
  89
  90                 /* Function Prototypes: */
  91                         /** Transmits a given string located in program space (FLASH) through the USART.
  92                          *
  93                          *  \param[in] FlashStringPtr  Pointer to a string located in program space.
  94                          */
  95                         void Serial_TxString_P(const char *FlashStringPtr) ATTR_NON_NULL_PTR_ARG(1);
  96
  97                         /** Transmits a given string located in SRAM memory through the USART.
  98                          *
  99                          *  \param[in] StringPtr  Pointer to a string located in SRAM space.
 100                          */
 101                         void Serial_TxString(const char *StringPtr) ATTR_NON_NULL_PTR_ARG(1);
 102
 103                 /* Inline Functions: */
 104                         /** Initializes the USART, ready for serial data transmission and reception. This initializes the interface to
 105                          *  standard 8-bit, no parity, 1 stop bit settings suitable for most applications.
 106                          *
 107                          *  \param[in] BaudRate     Serial baud rate, in bits per second.
 108                          *  \param[in] DoubleSpeed  Enables double speed mode when set, halving the sample time to double the baud rate.
 109                          */
 110                         static inline void Serial_Init(const uint32_t BaudRate, const bool DoubleSpeed)
 111                         {
 112                                 UCSR1A = (DoubleSpeed ? (1 << U2X1) : 0);
 113                                 UCSR1B = ((1 << TXEN1)  | (1 << RXEN1));
 114                                 UCSR1C = ((1 << UCSZ11) | (1 << UCSZ10));
 115
 116                                 DDRD  |= (1 << 3);
 117                                 PORTD |= (1 << 2);
 118
 119                                 UBRR1  = (DoubleSpeed ? SERIAL_2X_UBBRVAL(BaudRate) : SERIAL_UBBRVAL(BaudRate));
 120                         }
 121
 122                         /** Turns off the USART driver, disabling and returning used hardware to their default configuration. */
 123                         static inline void Serial_ShutDown(void)
 124                         {
 125                                 UCSR1A = 0;
 126                                 UCSR1B = 0;
 127                                 UCSR1C = 0;
 128
 129                                 DDRD  &= ~(1 << 3);
 130                                 PORTD &= ~(1 << 2);
 131
 132                                 UBRR1  = 0;
 133                         }
 134
 135                         /** Transmits a given byte through the USART.
 136                          *
 137                          *  \param[in] DataByte  Byte to transmit through the USART.
 138                          */
 139                         static inline void Serial_TxByte(const char DataByte)
 140                         {
 141                                 while (!(UCSR1A & (1 << UDRE1)));
 142                                 UDR1 = DataByte;
 143                         }
 144
 145                         /** Receives a byte from the USART.
 146                          *
 147                          *  \return Byte received from the USART.
 148                          */
 149                         static inline char Serial_RxByte(void)
 150                         {
 151                                 while (!(UCSR1A & (1 << RXC1)));
 152                                 return UDR1;
 153                         }
 154
 155         /* Disable C linkage for C++ Compilers: */
 156                 #if defined(__cplusplus)
 157                         }
 158                 #endif
 159
 160 #endif
 161
 162 /** @} */