LUFA/Drivers/Peripheral/Serial.h

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2009.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6       www.fourwalledcubicle.com
   7 */
   8
   9 /*
  10   Copyright 2009  Dean Camera (dean [at] fourwalledcubicle [dot] com)
  11
  12   Permission to use, copy, modify, and distribute this software
  13   and its documentation for any purpose and without fee is hereby
  14   granted, provided that the above copyright notice appear in all
  15   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  *
  33  *  Driver for the USART subsystem on supported USB AVRs.
  34  */
  35
  36 /** \ingroup Group_PeripheralDrivers
  37  *  @defgroup Group_Serial Serial USART Driver - LUFA/Drivers/Peripheral/Serial.h
  38  *
  39  *  \section Sec_Dependencies Module Source Dependencies
  40  *  The following files must be built with any user project that uses this module:
  41  *    - LUFA/Drivers/Peripheral/Serial.c
  42  *
  43  *  \section Module Description
  44  *  Functions, macros, variables, enums and types related to the setup of the USART for serial communications.
  45  *
  46  *  @{
  47  */
  48
  49 #ifndef __SERIAL_H__
  50 #define __SERIAL_H__
  51
  52         /* Includes: */
  53                 #include <avr/io.h>
  54                 #include <avr/pgmspace.h>
  55                 #include <stdbool.h>
  56
  57                 #include "../../Common/Common.h"
  58                 #include "../Misc/TerminalCodes.h"
  59
  60         /* Enable C linkage for C++ Compilers: */
  61                 #if defined(__cplusplus)
  62                         extern "C" {
  63                 #endif
  64
  65         /* Public Interface - May be used in end-application: */
  66                 /* Macros: */
  67                         /** Macro for calculating the baud value from a given baud rate when the U2X (double speed) bit is
  68                          *  not set.
  69                          */
  70                         #define SERIAL_UBBRVAL(baud)    (((F_CPU / 16) / baud) - 1)
  71
  72                         /** Macro for calculating the baud value from a given baud rate when the U2X (double speed) bit is
  73                          *  set.
  74                          */
  75                         #define SERIAL_2X_UBBRVAL(baud) (((F_CPU / 8) / baud) - 1)
  76
  77                 /* Pseudo-Function Macros: */
  78                         #if defined(__DOXYGEN__)
  79                                 /** Indicates whether a character has been received through the USART.
  80                                  *
  81                                  *  \return Boolean true if a character has been received, false otherwise
  82                                  */
  83                                 static inline bool Serial_IsCharReceived(void);
  84                         #else
  85                                 #define Serial_IsCharReceived() ((UCSR1A & (1 << RXC1)) ? true : false)
  86                         #endif
  87
  88                 /* Function Prototypes: */
  89                         /** Transmits a given string located in program space (FLASH) through the USART.
  90                          *
  91                          *  \param FlashStringPtr  Pointer to a string located in program space
  92                          */
  93                         void Serial_TxString_P(const char *FlashStringPtr) ATTR_NON_NULL_PTR_ARG(1);
  94
  95                         /** Transmits a given string located in SRAM memory through the USART.
  96                          *
  97                          *  \param StringPtr  Pointer to a string located in SRAM space
  98                          */
  99                         void Serial_TxString(const char *StringPtr) ATTR_NON_NULL_PTR_ARG(1);
 100
 101                 /* Inline Functions: */
 102                         /** Initializes the USART, ready for serial data transmission and reception. This initialises the interface to
 103                          *  standard 8-bit, no parity, 1 stop bit settings suitable for most applications.
 104                          *
 105                          *  \param BaudRate     Serial baud rate, in bits per second
 106                          *  \param DoubleSpeed  Enables double speed mode when set, halving the sample time to double the baud rate
 107                          */
 108                         static inline void Serial_Init(const uint32_t BaudRate, const bool DoubleSpeed)
 109                         {
 110                                 UCSR1A = (DoubleSpeed ? (1 << U2X1) : 0);
 111                                 UCSR1B = ((1 << TXEN1)  | (1 << RXEN1));
 112                                 UCSR1C = ((1 << UCSZ11) | (1 << UCSZ10));
 113
 114                                 DDRD  |= (1 << 3);
 115                                 PORTD |= (1 << 2);
 116
 117                                 UBRR1  = (DoubleSpeed ? SERIAL_2X_UBBRVAL(BaudRate) : SERIAL_UBBRVAL(BaudRate));
 118                         }
 119
 120                         /** Transmits a given byte through the USART.
 121                          *
 122                          *  \param DataByte  Byte to transmit through the USART
 123                          */
 124                         static inline void Serial_TxByte(const char DataByte)
 125                         {
 126                                 while (!(UCSR1A & (1 << UDRE1)));
 127                                 UDR1 = DataByte;
 128                         }
 129
 130                         /** Receives a byte from the USART.
 131                          *
 132                          *  \return Byte received from the USART
 133                          */
 134                         static inline char Serial_RxByte(void)
 135                         {
 136                                 while (!(UCSR1A & (1 << RXC1)));
 137                                 return UDR1;
 138                         }
 139
 140         /* Disable C linkage for C++ Compilers: */
 141                 #if defined(__cplusplus)
 142                         }
 143                 #endif
 144
 145 #endif
 146
 147 /** @} */