#ifndef USART_H #define USART_H /************************************************************************ Title: Interrupt UART library with receive/transmit circular buffers Author: Andy Gock Software: AVR-GCC 4.1, AVR Libc 1.4 Hardware: any AVR with built-in UART, tested on AT90S8515 & ATmega8 at 4 Mhz License: GNU General Public License Usage: see README.md and Doxygen manual Based on original library by Peter Fluery, Tim Sharpe, Nicholas Zambetti. https://github.com/andygock/avr-uart LICENSE: Copyright (C) 2012 Andy Gock Copyright (C) 2006 Peter Fleury This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. ************************************************************************/ /************************************************************************ uart_available, uart_flush, uart1_available, and uart1_flush functions were adapted from the Arduino HardwareSerial.h library by Tim Sharpe on 11 Jan 2009. The license info for HardwareSerial.h is as follows: HardwareSerial.h - Hardware serial library for Wiring Copyright (c) 2006 Nicholas Zambetti. All right reserved. This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA ************************************************************************/ /** * @defgroup avr-uart UART Library * @code #include <uart.h> @endcode * * @brief Interrupt UART library using the built-in UART with transmit and receive circular buffers. * @see README.md * * This library can be used to transmit and receive data through the built in UART. * * An interrupt is generated when the UART has finished transmitting or * receiving a byte. The interrupt handling routines use circular buffers * for buffering received and transmitted data. * * The UART_RXn_BUFFER_SIZE and UART_TXn_BUFFER_SIZE constants define * the size of the circular buffers in bytes. Note that these constants must be a power of 2. * * You need to define these buffer sizes as a symbol in your compiler settings or in uart.h * * See README.md for more detailed information. Especially that relating to symbols: USARTn_ENABLED and USARTn_LARGE_BUFFER * * @author Andy Gock <andy@gock.net> * @note Based on Atmel Application Note AVR306 and original library by Peter Fleury and Tim Sharpe. */ /**@{*/ #include <stdint.h> #include <avr/io.h> #if (__GNUC__ * 100 + __GNUC_MINOR__) < 304 #error "This library requires AVR-GCC 3.4 or later, update to newer AVR-GCC compiler !" #endif /* * constants and macros */ /* Enable USART 1, 2, 3 as required */ /* Can be defined in compiler symbol setup with -D option (preferred) */ #ifndef USART0_ENABLED #define USART0_ENABLED /**< Enable USART0 */ #endif //#define USART1_ENABLED //#define USART2_ENABLED //#define USART3_ENABLED /* Set size of receive and transmit buffers */ #ifndef UART_RX0_BUFFER_SIZE #define UART_RX0_BUFFER_SIZE 128 /**< Size of the circular receive buffer, must be power of 2 */ #endif #ifndef UART_RX1_BUFFER_SIZE #define UART_RX1_BUFFER_SIZE 128 /**< Size of the circular receive buffer, must be power of 2 */ #endif #ifndef UART_RX2_BUFFER_SIZE #define UART_RX2_BUFFER_SIZE 128 /**< Size of the circular receive buffer, must be power of 2 */ #endif #ifndef UART_RX3_BUFFER_SIZE #define UART_RX3_BUFFER_SIZE 128 /**< Size of the circular receive buffer, must be power of 2 */ #endif #ifndef UART_TX0_BUFFER_SIZE #define UART_TX0_BUFFER_SIZE 128 /**< Size of the circular transmit buffer, must be power of 2 */ #endif #ifndef UART_TX1_BUFFER_SIZE #define UART_TX1_BUFFER_SIZE 128 /**< Size of the circular transmit buffer, must be power of 2 */ #endif #ifndef UART_TX2_BUFFER_SIZE #define UART_TX2_BUFFER_SIZE 128 /**< Size of the circular transmit buffer, must be power of 2 */ #endif #ifndef UART_TX3_BUFFER_SIZE #define UART_TX3_BUFFER_SIZE 128 /**< Size of the circular transmit buffer, must be power of 2 */ #endif /* Check buffer sizes are not too large for 8-bit positioning */ #if (UART_RX0_BUFFER_SIZE > 256 & !defined(USART0_LARGE_BUFFER)) #error "Buffer too large, please use -DUSART0_LARGE_BUFFER switch in compiler options" #endif #if (UART_RX1_BUFFER_SIZE > 256 & !defined(USART1_LARGE_BUFFER)) #error "Buffer too large, please use -DUSART1_LARGE_BUFFER switch in compiler options" #endif #if (UART_RX2_BUFFER_SIZE > 256 & !defined(USART2_LARGE_BUFFER)) #error "Buffer too large, please use -DUSART2_LARGE_BUFFER switch in compiler options" #endif #if (UART_RX3_BUFFER_SIZE > 256 & !defined(USART3_LARGE_BUFFER)) #error "Buffer too large, please use -DUSART3_LARGE_BUFFER switch in compiler options" #endif /* Check buffer sizes are not too large for *_LARGE_BUFFER operation (16-bit positioning) */ #if (UART_RX0_BUFFER_SIZE > 32768) #error "Buffer too large, maximum allowed is 32768 bytes" #endif #if (UART_RX1_BUFFER_SIZE > 32768) #error "Buffer too large, maximum allowed is 32768 bytes" #endif #if (UART_RX2_BUFFER_SIZE > 32768) #error "Buffer too large, maximum allowed is 32768 bytes" #endif #if (UART_RX3_BUFFER_SIZE > 32768) #error "Buffer too large, maximum allowed is 32768 bytes" #endif /** @brief UART Baudrate Expression * @param xtalCpu system clock in Mhz, e.g. 4000000L for 4Mhz * @param baudRate baudrate in bps, e.g. 1200, 2400, 9600 */ #define UART_BAUD_SELECT(baudRate,xtalCpu) (((xtalCpu)+8UL*(baudRate))/(16UL*(baudRate))-1UL) /** @brief UART Baudrate Expression for ATmega double speed mode * @param xtalCpu system clock in Mhz, e.g. 4000000L for 4Mhz * @param baudRate baudrate in bps, e.g. 1200, 2400, 9600 */ #define UART_BAUD_SELECT_DOUBLE_SPEED(baudRate,xtalCpu) ((((xtalCpu)+4UL*(baudRate))/(8UL*(baudRate))-1)|0x8000) /* test if the size of the circular buffers fits into SRAM */ #if defined(USART0_ENABLED) && ( (UART_RX0_BUFFER_SIZE+UART_TX0_BUFFER_SIZE) >= (RAMEND-0x60)) #error "size of UART_RX0_BUFFER_SIZE + UART_TX0_BUFFER_SIZE larger than size of SRAM" #endif #if defined(USART1_ENABLED) && ( (UART_RX1_BUFFER_SIZE+UART_TX1_BUFFER_SIZE) >= (RAMEND-0x60)) #error "size of UART_RX1_BUFFER_SIZE + UART_TX1_BUFFER_SIZE larger than size of SRAM" #endif #if defined(USART2_ENABLED) && ( (UART_RX2_BUFFER_SIZE+UART_RX2_BUFFER_SIZE) >= (RAMEND-0x60)) #error "size of UART_RX2_BUFFER_SIZE + UART_TX2_BUFFER_SIZE larger than size of SRAM" #endif #if defined(USART3_ENABLED) && ( (UART_RX3_BUFFER_SIZE+UART_RX3_BUFFER_SIZE) >= (RAMEND-0x60)) #error "size of UART_RX3_BUFFER_SIZE + UART_TX3_BUFFER_SIZE larger than size of SRAM" #endif /* ** high byte error return code of uart_getc() */ #define UART_FRAME_ERROR 0x0800 /**< Framing Error by UART */ #define UART_OVERRUN_ERROR 0x0400 /**< Overrun condition by UART */ #define UART_BUFFER_OVERFLOW 0x0200 /**< receive ringbuffer overflow */ #define UART_NO_DATA 0x0100 /**< no receive data available */ /* Macros, to allow use of legacy names */ /** @brief Macro to initialize USART0 (only available on selected ATmegas) @see uart0_init */ #define uart_init(b) uart0_init(b) /** @brief Macro to get received byte of USART0 from ringbuffer. (only available on selected ATmega) @see uart0_getc */ #define uart_getc() uart0_getc() /** @brief Macro to peek at next byte in USART0 ringbuffer */ #define uart_peek() uart0_peek() /** @brief Macro to put byte to ringbuffer for transmitting via USART0 (only available on selected ATmega) @see uart0_putc */ #define uart_putc(d) uart0_putc(d) /** @brief Macro to put string to ringbuffer for transmitting via USART0 (only available on selected ATmega) @see uart0_puts */ #define uart_puts(s) uart0_puts(s) /** @brief Macro to put string from program memory to ringbuffer for transmitting via USART0 (only available on selected ATmega) @see uart0_puts_p */ #define uart_puts_p(s) uart0_puts_p(s) /** @brief Macro to return number of bytes waiting in the receive buffer of USART0 @see uart0_available */ #define uart_available() uart0_available() /** @brief Macro to flush bytes waiting in receive buffer of USART0 @see uart0_flush */ #define uart_flush() uart0_flush() /* ** function prototypes */ /** @brief Initialize UART and set baudrate @param baudrate Specify baudrate using macro UART_BAUD_SELECT() @return none */ /*extern*/void uart0_init(uint16_t baudrate); /** * @brief Get received byte from ringbuffer * * Returns in the lower byte the received character and in the * higher byte the last receive error. * UART_NO_DATA is returned when no data is available. * * @return lower byte: received byte from ringbuffer * @return higher byte: last receive status * - \b 0 successfully received data from UART * - \b UART_NO_DATA * <br>no receive data available * - \b UART_BUFFER_OVERFLOW * <br>Receive ringbuffer overflow. * We are not reading the receive buffer fast enough, * one or more received character have been dropped * - \b UART_OVERRUN_ERROR * <br>Overrun condition by UART. * A character already present in the UART UDR register was * not read by the interrupt handler before the next character arrived, * one or more received characters have been dropped. * - \b UART_FRAME_ERROR * <br>Framing Error by UART */ /*extern*/uint16_t uart0_getc(void); /** * @brief Peek at next byte in ringbuffer * * Returns the next byte (character) of incoming UART data without removing it from the * internal ring buffer. That is, successive calls to uartN_peek() will return the same * character, as will the next call to uartN_getc(). * * UART_NO_DATA is returned when no data is available. * * @return lower byte: next byte in ringbuffer * @return higher byte: last receive status * - \b 0 successfully received data from UART * - \b UART_NO_DATA * <br>no receive data available * - \b UART_BUFFER_OVERFLOW * <br>Receive ringbuffer overflow. * We are not reading the receive buffer fast enough, * one or more received character have been dropped * - \b UART_OVERRUN_ERROR * <br>Overrun condition by UART. * A character already present in the UART UDR register was * not read by the interrupt handler before the next character arrived, * one or more received characters have been dropped. * - \b UART_FRAME_ERROR * <br>Framing Error by UART */ /*extern*/uint16_t uart0_peek(void); /** * @brief Put byte to ringbuffer for transmitting via UART * @param data byte to be transmitted * @return none */ /*extern*/void uart0_putc(uint8_t data); /** * @brief Put string to ringbuffer for transmitting via UART * * The string is buffered by the uart library in a circular buffer * and one character at a time is transmitted to the UART using interrupts. * Blocks if it can not write the whole string into the circular buffer. * * @param s string to be transmitted * @return none */ /*extern*/void uart0_puts(const char *s); /** * @brief Put string from program memory to ringbuffer for transmitting via UART. * * The string is buffered by the uart library in a circular buffer * and one character at a time is transmitted to the UART using interrupts. * Blocks if it can not write the whole string into the circular buffer. * * @param s program memory string to be transmitted * @return none * @see uart0_puts_P */ /*extern*/void uart0_puts_p(const char *s); /** * @brief Macro to automatically put a string constant into program memory * \param __s string in program memory */ #define uart_puts_P(__s) uart0_puts_p(PSTR(__s)) /** @brief Macro to automatically put a string constant into program memory */ #define uart0_puts_P(__s) uart0_puts_p(PSTR(__s)) /** * @brief Return number of bytes waiting in the receive buffer * @return bytes waiting in the receive buffer */ /*extern*/uint16_t uart0_available(void); /** * @brief Flush bytes waiting in receive buffer */ /*extern*/void uart0_flush(void); /** @brief Initialize USART1 (only available on selected ATmegas) @see uart_init */ /*extern*/void uart1_init(uint16_t baudrate); /** @brief Get received byte of USART1 from ringbuffer. (only available on selected ATmega) @see uart_getc */ /*extern*/uint16_t uart1_getc(void); /** @brief Peek at next byte in USART1 ringbuffer */ /*extern*/uint16_t uart1_peek(void); /** @brief Put byte to ringbuffer for transmitting via USART1 (only available on selected ATmega) @see uart_putc */ /*extern*/void uart1_putc(uint8_t data); /** @brief Put string to ringbuffer for transmitting via USART1 (only available on selected ATmega) @see uart_puts */ /*extern*/void uart1_puts(const char *s); /** @brief Put string from program memory to ringbuffer for transmitting via USART1 (only available on selected ATmega) @see uart_puts_p */ /*extern*/void uart1_puts_p(const char *s); /** @brief Macro to automatically put a string constant into program memory of USART1 @see uart1_puts_p */ #define uart1_puts_P(__s) uart1_puts_p(PSTR(__s)) /** @brief Return number of bytes waiting in the receive buffer of USART1 */ /*extern*/uint16_t uart1_available(void); /** @brief Flush bytes waiting in receive buffer of USART1 */ /*extern*/void uart1_flush(void); /** @brief Initialize USART2 (only available on selected ATmegas) @see uart_init */ /*extern*/void uart2_init(uint16_t baudrate); /** @brief Get received byte of USART2 from ringbuffer. (only available on selected ATmega) @see uart_getc */ /*extern*/uint16_t uart2_getc(void); /** @brief Peek at next byte in USART2 ringbuffer */ /*extern*/uint16_t uart2_peek(void); /** @brief Put byte to ringbuffer for transmitting via USART2 (only available on selected ATmega) @see uart_putc */ /*extern*/void uart2_putc(uint8_t data); /** @brief Put string to ringbuffer for transmitting via USART2 (only available on selected ATmega) @see uart_puts */ /*extern*/void uart2_puts(const char *s); /** @brief Put string from program memory to ringbuffer for transmitting via USART2 (only available on selected ATmega) @see uart_puts_p */ /*extern*/void uart2_puts_p(const char *s); /** @brief Macro to automatically put a string constant into program memory of USART2 @see uart2_puts_p */ #define uart2_puts_P(__s) uart2_puts_p(PSTR(__s)) /** @brief Return number of bytes waiting in the receive buffer of USART2 */ /*extern*/uint16_t uart2_available(void); /** @brief Flush bytes waiting in receive buffer of USART2 */ /*extern*/void uart2_flush(void); /** @brief Initialize USART3 (only available on selected ATmegas) @see uart_init */ /*extern*/void uart3_init(uint16_t baudrate); /** @brief Get received byte of USART3 from ringbuffer. (only available on selected ATmega) @see uart_getc */ /*extern*/uint16_t uart3_getc(void); /** @brief Peek at next byte in USART3 ringbuffer */ /*extern*/uint16_t uart3_peek(void); /** @brief Put byte to ringbuffer for transmitting via USART3 (only available on selected ATmega) @see uart_putc */ /*extern*/void uart3_putc(uint8_t data); /** @brief Put string to ringbuffer for transmitting via USART3 (only available on selected ATmega) @see uart_puts */ /*extern*/void uart3_puts(const char *s); /** @brief Put string from program memory to ringbuffer for transmitting via USART3 (only available on selected ATmega) @see uart_puts_p */ /*extern*/void uart3_puts_p(const char *s); /** @brief Macro to automatically put a string constant into program memory of USART3 @see uart3_puts_p */ #define uart3_puts_P(__s) uart3_puts_p(PSTR(__s)) /** @brief Return number of bytes waiting in the receive buffer of USART3 */ /*extern*/uint16_t uart3_available(void); /** @brief Flush bytes waiting in receive buffer of USART3 */ /*extern*/void uart3_flush(void); /**@}*/ #endif // UART_H