Add more const-ness to the stream endpoint/pipe functions where possible.
[pub/USBasp.git] / LUFA / Drivers / Peripheral / Serial.h
index 51600f4..e7c2fa0 100644 (file)
-/*\r
-             LUFA Library\r
-     Copyright (C) Dean Camera, 2010.\r
-              \r
-  dean [at] fourwalledcubicle [dot] com\r
-      www.fourwalledcubicle.com\r
-*/\r
-\r
-/*\r
-  Copyright 2010  Dean Camera (dean [at] fourwalledcubicle [dot] com)\r
-\r
-  Permission to use, copy, modify, distribute, and sell this \r
-  software and its documentation for any purpose is hereby granted\r
-  without fee, provided that the above copyright notice appear in \r
-  all copies and that both that the copyright notice and this\r
-  permission notice and warranty disclaimer appear in supporting \r
-  documentation, and that the name of the author not be used in \r
-  advertising or publicity pertaining to distribution of the \r
-  software without specific, written prior permission.\r
-\r
-  The author disclaim all warranties with regard to this\r
-  software, including all implied warranties of merchantability\r
-  and fitness.  In no event shall the author be liable for any\r
-  special, indirect or consequential damages or any damages\r
-  whatsoever resulting from loss of use, data or profits, whether\r
-  in an action of contract, negligence or other tortious action,\r
-  arising out of or in connection with the use or performance of\r
-  this software.\r
-*/\r
-\r
-/** \file\r
- *\r
- *  This file is the master dispatch header file for the device-specific USART driver, for AVRs containing a\r
- *  USART.\r
- *\r
- *  User code should include this file, which will in turn include the correct USART driver header file for\r
- *  the currently selected AVR model.\r
- */\r
\r
-/** \ingroup Group_PeripheralDrivers\r
- *  @defgroup Group_Serial Serial USART Driver - LUFA/Drivers/Peripheral/Serial.h\r
- *\r
- *  \section Sec_Dependencies Module Source Dependencies\r
- *  The following files must be built with any user project that uses this module:\r
- *    - LUFA/Drivers/Peripheral/Serial.c\r
- *\r
- *  \section Module Description\r
- *  Hardware serial USART driver. This module provides an easy to use driver for\r
- *  the setup of and transfer of data over the AVR's USART port.\r
- *\r
- *  @{\r
- */\r
\r
-#ifndef __SERIAL_H__\r
-#define __SERIAL_H__\r
-\r
-       /* Macros: */\r
-       #if !defined(__DOXYGEN__)\r
-               #define __INCLUDE_FROM_SERIAL_H\r
-       #endif\r
-\r
-       /* Includes: */\r
-               #if defined(__AVR32__)\r
-                       #include "AVR32/Serial.h"\r
-               #else\r
-                       #include "AVRU4U6U7/Serial.h"           \r
-               #endif\r
-               \r
-               #include "../../Common/Common.h"\r
-               #include "../Misc/TerminalCodes.h"\r
-\r
-       /* Enable C linkage for C++ Compilers: */\r
-               #if defined(__cplusplus)\r
-                       extern "C" {\r
-               #endif\r
-\r
-       /* Public Interface - May be used in end-application: */\r
-               /* Function Prototypes: */\r
-                       /** Transmits a given string located in program space (FLASH) through the USART.\r
-                        *\r
-                        *  \param[in] FlashStringPtr  Pointer to a string located in program space\r
-                        */\r
-                       void Serial_TxString_P(const char *FlashStringPtr) ATTR_NON_NULL_PTR_ARG(1);\r
-\r
-                       /** Transmits a given string located in SRAM memory through the USART.\r
-                        *\r
-                        *  \param[in] StringPtr  Pointer to a string located in SRAM space\r
-                        */\r
-                       void Serial_TxString(const char *StringPtr) ATTR_NON_NULL_PTR_ARG(1);\r
-\r
-       /* Disable C linkage for C++ Compilers: */\r
-               #if defined(__cplusplus)\r
-                       }\r
-               #endif\r
-               \r
-#endif\r
-\r
-/** @} */\r
+/*
+             LUFA Library
+     Copyright (C) Dean Camera, 2011.
+
+  dean [at] fourwalledcubicle [dot] com
+           www.lufa-lib.org
+*/
+
+/*
+  Copyright 2011  Dean Camera (dean [at] fourwalledcubicle [dot] com)
+
+  Permission to use, copy, modify, distribute, and sell this
+  software and its documentation for any purpose is hereby granted
+  without fee, provided that the above copyright notice appear in
+  all copies and that both that the copyright notice and this
+  permission notice and warranty disclaimer appear in supporting
+  documentation, and that the name of the author not be used in
+  advertising or publicity pertaining to distribution of the
+  software without specific, written prior permission.
+
+  The author disclaim all warranties with regard to this
+  software, including all implied warranties of merchantability
+  and fitness.  In no event shall the author be liable for any
+  special, indirect or consequential damages or any damages
+  whatsoever resulting from loss of use, data or profits, whether
+  in an action of contract, negligence or other tortious action,
+  arising out of or in connection with the use or performance of
+  this software.
+*/
+
+/** \file
+ *  \brief Master include file for the USART peripheral driver.
+ *
+ *  Driver for the USART subsystem on supported USB AVRs.
+ */
+
+/** \ingroup Group_PeripheralDrivers
+ *  @defgroup Group_Serial Serial USART Driver - LUFA/Drivers/Peripheral/Serial.h
+ *
+ *  \section Sec_Dependencies Module Source Dependencies
+ *  The following files must be built with any user project that uses this module:
+ *    - LUFA/Drivers/Peripheral/Serial.c <i>(Makefile source module name: LUFA_SRC_SERIAL)</i>
+ *
+ *  \section Sec_ModDescription Module Description
+ *  Hardware serial USART driver. This module provides an easy to use driver for
+ *  the setup of and transfer of data over the AVR's USART port.
+ *
+ *  \section Sec_ExampleUsage Example Usage
+ *  The following snippet is an example of how this module may be used within a typical
+ *  application.
+ *
+ *  \code
+ *      // Initialise the serial USART driver before first use, with 9600 baud (and no double-speed mode)
+ *      Serial_Init(9600, false);
+ *
+ *      // Send a string through the USART
+ *      Serial_TxString("Test String\r\n");
+ *
+ *      // Receive a byte through the USART
+ *      uint8_t DataByte = Serial_RxByte();
+ *  \endcode
+ *
+ *  @{
+ */
+
+#ifndef __SERIAL_H__
+#define __SERIAL_H__
+
+       /* Includes: */
+               #include <avr/io.h>
+               #include <avr/pgmspace.h>
+               #include <stdbool.h>
+               #include <stdio.h>
+
+               #include "../../Common/Common.h"
+               #include "../Misc/TerminalCodes.h"
+
+       /* Enable C linkage for C++ Compilers: */
+               #if defined(__cplusplus)
+                       extern "C" {
+               #endif
+
+       /* Private Interface - For use in library only: */
+       #if !defined(__DOXYGEN__)
+               /* External Variables: */
+                       extern FILE USARTSerialStream;
+       
+               /* Function Prototypes: */
+                       int Serial_putchar(char DataByte,
+                                          FILE *Stream);
+                       int Serial_getchar(FILE *Stream);
+                       int Serial_getchar_Blocking(FILE *Stream);
+       #endif
+
+       /* Public Interface - May be used in end-application: */
+               /* Macros: */
+                       /** Macro for calculating the baud value from a given baud rate when the U2X (double speed) bit is
+                        *  not set.
+                        */
+                       #define SERIAL_UBBRVAL(baud)    ((((F_CPU / 16) + (baud / 2)) / (baud)) - 1)
+
+                       /** Macro for calculating the baud value from a given baud rate when the U2X (double speed) bit is
+                        *  set.
+                        */
+                       #define SERIAL_2X_UBBRVAL(baud) ((((F_CPU / 8) + (baud / 2)) / (baud)) - 1)
+
+               /* Function Prototypes: */
+                       /** Transmits a given string located in program space (FLASH) through the USART.
+                        *
+                        *  \param[in] FlashStringPtr  Pointer to a string located in program space.
+                        */
+                       void Serial_SendString_P(const char* FlashStringPtr) ATTR_NON_NULL_PTR_ARG(1);
+
+                       /** Transmits a given string located in SRAM memory through the USART.
+                        *
+                        *  \param[in] StringPtr  Pointer to a string located in SRAM space.
+                        */
+                       void Serial_SendString(const char* StringPtr) ATTR_NON_NULL_PTR_ARG(1);
+                       
+                       /** Transmits a given buffer located in SRAM memory through the USART.
+                        *
+                        *  \param[in] Buffer  Pointer to a buffer containing the data to send.
+                        *  \param[in] Length  Length of the data to send, in bytes.
+                        */
+                       void Serial_SendData(const uint8_t* Buffer, uint16_t Length) ATTR_NON_NULL_PTR_ARG(1);
+
+               /* Inline Functions: */
+                       /** Initializes the USART, ready for serial data transmission and reception. This initializes the interface to
+                        *  standard 8-bit, no parity, 1 stop bit settings suitable for most applications.
+                        *
+                        *  \param[in] BaudRate     Serial baud rate, in bits per second.
+                        *  \param[in] DoubleSpeed  Enables double speed mode when set, halving the sample time to double the baud rate.
+                        */
+                       static inline void Serial_Init(const uint32_t BaudRate,
+                                                      const bool DoubleSpeed)
+                       {
+                               UBRR1  = (DoubleSpeed ? SERIAL_2X_UBBRVAL(BaudRate) : SERIAL_UBBRVAL(BaudRate));
+
+                               UCSR1C = ((1 << UCSZ11) | (1 << UCSZ10));
+                               UCSR1A = (DoubleSpeed ? (1 << U2X1) : 0);
+                               UCSR1B = ((1 << TXEN1)  | (1 << RXEN1));
+
+                               DDRD  |= (1 << 3);
+                               PORTD |= (1 << 2);
+                       }
+
+                       /** Turns off the USART driver, disabling and returning used hardware to their default configuration. */
+                       static inline void Serial_Disable(void)
+                       {
+                               UCSR1B = 0;
+                               UCSR1A = 0;
+                               UCSR1C = 0;
+
+                               UBRR1  = 0;
+
+                               DDRD  &= ~(1 << 3);
+                               PORTD &= ~(1 << 2);
+                       }
+
+                       /** Creates a standard character stream from the USART so that it can be used with all the regular functions
+                        *  in the avr-libc \c <stdio.h> library that accept a \c FILE stream as a destination (e.g. \c fprintf). The created
+                        *  stream is bidirectional and can be used for both input and output functions.
+                        *
+                        *  Reading data from this stream is non-blocking, i.e. in most instances, complete strings cannot be read in by a single
+                        *  fetch, as the endpoint will not be ready at some point in the transmission, aborting the transfer. However, this may
+                        *  be used when the read data is processed byte-per-bye (via \c getc()) or when the user application will implement its own
+                        *  line buffering.
+                        *
+                        *  \param[in,out] Stream  Pointer to a FILE structure where the created stream should be placed, if \c NULL stdio
+                        *                         and stdin will be configured to use the USART.
+                        *
+                        *  \pre The USART must first be configured via a call to \ref Serial_Init() before the stream is used.
+                        */
+                       static inline void Serial_CreateStream(FILE* Stream)
+                       {
+                               if (!(Stream))
+                               {
+                                       Stream = &USARTSerialStream;
+                                       stdin  = Stream;
+                                       stdout = Stream;
+                               }
+                       
+                               *Stream = (FILE)FDEV_SETUP_STREAM(Serial_putchar, Serial_getchar, _FDEV_SETUP_RW);
+                       }
+
+                       /** Identical to \ref Serial_CreateStream(), except that reads are blocking until the calling stream function terminates
+                        *  the transfer.
+                        *
+                        *  \param[in,out] Stream  Pointer to a FILE structure where the created stream should be placed, if \c NULL stdio
+                        *                         and stdin will be configured to use the USART.
+                        *
+                        *  \pre The USART must first be configured via a call to \ref Serial_Init() before the stream is used.
+                        */
+                       static inline void Serial_CreateBlockingStream(FILE* Stream)
+                       {
+                               if (!(Stream))
+                               {
+                                       Stream = &USARTSerialStream;
+                                       stdin  = Stream;
+                                       stdout = Stream;
+                               }
+
+                               *Stream = (FILE)FDEV_SETUP_STREAM(Serial_putchar, Serial_getchar_Blocking, _FDEV_SETUP_RW);
+                       }
+
+                       /** Indicates whether a character has been received through the USART.
+                        *
+                        *  \return Boolean \c true if a character has been received, \c false otherwise.
+                        */
+                       static inline bool Serial_IsCharReceived(void) ATTR_WARN_UNUSED_RESULT ATTR_ALWAYS_INLINE;
+                       static inline bool Serial_IsCharReceived(void)
+                       {
+                               return ((UCSR1A & (1 << RXC1)) ? true : false);
+                       }
+
+                       /** Transmits a given byte through the USART.
+                        *
+                        *  \param[in] DataByte  Byte to transmit through the USART.
+                        */
+                       static inline void Serial_SendByte(const char DataByte) ATTR_ALWAYS_INLINE;
+                       static inline void Serial_SendByte(const char DataByte)
+                       {
+                               while (!(UCSR1A & (1 << UDRE1)));
+                               UDR1 = DataByte;
+                       }
+
+                       /** Receives the next byte from the USART.
+                        *
+                        *  \return Next byte received from the USART, or a negative value if no byte has been received.
+                        */
+                       static inline int16_t Serial_ReceiveByte(void) ATTR_ALWAYS_INLINE;
+                       static inline int16_t Serial_ReceiveByte(void)
+                       {
+                               if (!(Serial_IsCharReceived()))
+                                 return -1;
+                               
+                               return UDR1;
+                       }
+
+       /* Disable C linkage for C++ Compilers: */
+               #if defined(__cplusplus)
+                       }
+               #endif
+
+#endif
+
+/** @} */
+