From e9a73bbb3c14af340999f70146747787785f4fee Mon Sep 17 00:00:00 2001 From: Tim Redfern Date: Mon, 19 Dec 2011 18:20:33 +0000 Subject: initial commit --- electic_streaming328p/uart.h | 195 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 195 insertions(+) create mode 100644 electic_streaming328p/uart.h (limited to 'electic_streaming328p/uart.h') diff --git a/electic_streaming328p/uart.h b/electic_streaming328p/uart.h new file mode 100644 index 0000000..579c77d --- /dev/null +++ b/electic_streaming328p/uart.h @@ -0,0 +1,195 @@ +#ifndef UART_H +#define UART_H +/************************************************************************ +Title: Interrupt UART library with receive/transmit circular buffers +Author: Peter Fleury http://jump.to/fleury +File: $Id: uart.h,v 1.8.2.1 2007/07/01 11:14:38 peter Exp $ +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 Doxygen manual + +LICENSE: + 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. + +************************************************************************/ + +/** + * @defgroup pfleury_uart UART Library + * @code #include @endcode + * + * @brief Interrupt UART library using the built-in UART with transmit and receive circular buffers. + * + * 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_RX_BUFFER_SIZE and UART_TX_BUFFER_SIZE constants define + * the size of the circular buffers in bytes. Note that these constants must be a power of 2. + * You may need to adapt this constants to your target and your application by adding + * CDEFS += -DUART_RX_BUFFER_SIZE=nn -DUART_RX_BUFFER_SIZE=nn to your Makefile. + * + * @note Based on Atmel Application Note AVR306 + * @author Peter Fleury pfleury@gmx.ch http://jump.to/fleury + */ + +/**@{*/ + + +#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 +*/ + +/** @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)/((baudRate)*16l)-1) + +/** @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)/((baudRate)*8l)-1)|0x8000) + + +/** Size of the circular receive buffer, must be power of 2 */ +#ifndef UART_RX_BUFFER_SIZE +#define UART_RX_BUFFER_SIZE 32 +#endif +/** Size of the circular transmit buffer, must be power of 2 */ +#ifndef UART_TX_BUFFER_SIZE +#define UART_TX_BUFFER_SIZE 32 +#endif + +/* test if the size of the circular buffers fits into SRAM */ +#if ( (UART_RX_BUFFER_SIZE+UART_TX_BUFFER_SIZE) >= (RAMEND-0x60 ) ) +#error "size of UART_RX_BUFFER_SIZE + UART_TX_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 */ + + +/* +** function prototypes +*/ + +/** + @brief Initialize UART and set baudrate + @param baudrate Specify baudrate using macro UART_BAUD_SELECT() + @return none +*/ +extern void uart_init(unsigned int 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. + * + * @param void + * @return lower byte: received byte from ringbuffer + * @return higher byte: last receive status + * - \b 0 successfully received data from UART + * - \b UART_NO_DATA + *
no receive data available + * - \b UART_BUFFER_OVERFLOW + *
Receive ringbuffer overflow. + * We are not reading the receive buffer fast enough, + * one or more received character have been dropped + * - \b UART_OVERRUN_ERROR + *
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 + *
Framing Error by UART + */ +extern unsigned int uart_getc(void); + + +/** + * @brief Put byte to ringbuffer for transmitting via UART + * @param data byte to be transmitted + * @return none + */ +extern void uart_putc(unsigned char 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 uart_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 uart_puts_P + */ +extern void uart_puts_p(const char *s ); + +/** + * @brief Macro to automatically put a string constant into program memory + */ +#define uart_puts_P(__s) uart_puts_p(PSTR(__s)) + + + +/** @brief Initialize USART1 (only available on selected ATmegas) @see uart_init */ +extern void uart1_init(unsigned int baudrate); +/** @brief Get received byte of USART1 from ringbuffer. (only available on selected ATmega) @see uart_getc */ +extern unsigned int uart1_getc(void); +/** @brief Put byte to ringbuffer for transmitting via USART1 (only available on selected ATmega) @see uart_putc */ +extern void uart1_putc(unsigned char 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 */ +#define uart1_puts_P(__s) uart1_puts_p(PSTR(__s)) + +/**@}*/ + + +#endif +// UART_H + -- cgit v1.2.3