diff --git a/examples/stm32/f0/stm32f0-discovery/usart_stdio/Makefile b/examples/stm32/f0/stm32f0-discovery/usart_stdio/Makefile new file mode 100644 index 0000000..2c14613 --- /dev/null +++ b/examples/stm32/f0/stm32f0-discovery/usart_stdio/Makefile @@ -0,0 +1,29 @@ +## +## This file is part of the libopencm3 project. +## +## Copyright (C) 2009 Uwe Hermann +## +## 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 3 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, see . +## + +BINARY = usart_stdio + +LDSCRIPT = ../stm32f0-discovery.ld + +#using newlib-nano +CFLAGS += --specs=nano.specs +LDFLAGS += --specs=nano.specs + +include ../../Makefile.include + diff --git a/examples/stm32/f0/stm32f0-discovery/usart_stdio/README b/examples/stm32/f0/stm32f0-discovery/usart_stdio/README new file mode 100644 index 0000000..8b888c1 --- /dev/null +++ b/examples/stm32/f0/stm32f0-discovery/usart_stdio/README @@ -0,0 +1,11 @@ +------------------------------------------------------------------------------ +README +------------------------------------------------------------------------------ + +This example program sends some characters on USART1 on the +ST STM32F0DISCOVERY eval board. PA9 + +The terminal settings for the receiving device/PC are 38400 8n1. + +The sending is done using newlib-nano library in a blocking way in the code. + diff --git a/examples/stm32/f0/stm32f0-discovery/usart_stdio/usart_stdio.c b/examples/stm32/f0/stm32f0-discovery/usart_stdio/usart_stdio.c new file mode 100644 index 0000000..2bc1484 --- /dev/null +++ b/examples/stm32/f0/stm32f0-discovery/usart_stdio/usart_stdio.c @@ -0,0 +1,119 @@ +/* + * This file is part of the libopencm3 project. + * + * Copyright (C) 2009 Uwe Hermann + * Copyright (C) 2011 Stephen Caudle + * + * 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 3 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, see . + */ + +#include +#include +#include +#include +#include +#include +#include + +static ssize_t _iord(void *_cookie, char *_buf,size_t _n); +static ssize_t _iowr(void *_cookie,const char *_buf, size_t _n); + +static ssize_t _iord(void *_cookie, char *_buf,size_t _n) +{ + /* dont support reading now */ + (void)_cookie; + (void)_buf; + (void)_n; + return 0; +} + +static ssize_t _iowr(void *_cookie,const char *_buf, size_t _n) +{ + uint32_t dev = (uint32_t)_cookie; + + int written = 0; + while (_n-- > 0) { + usart_send_blocking(dev, *_buf++); + written++; + }; + return written; +} + + +static FILE* usart_setup(uint32_t dev) +{ + /* Setup USART2 parameters. */ + usart_set_baudrate(dev, 38400); + usart_set_databits(dev, 8); + usart_set_parity(dev, USART_PARITY_NONE); + usart_set_stopbits(dev, USART_CR2_STOP_1_0BIT); + usart_set_mode(dev, USART_MODE_TX_RX); + usart_set_flow_control(dev, USART_FLOWCONTROL_NONE); + + /* Finally enable the USART. */ + usart_enable(dev); + + cookie_io_functions_t stub = { _iord, _iowr, NULL, NULL }; + FILE *fp = fopencookie((void *)dev,"rw+",stub); + /* Do not buffer the serial line */ + setvbuf(fp, NULL, _IONBF, 0); + return fp; + +} + +static void clock_setup(void) +{ + /* Enable GPIOC clock for LED & USARTs. */ + rcc_periph_clock_enable(RCC_GPIOC); + rcc_periph_clock_enable(RCC_GPIOA); + + /* Enable clocks for USART2. */ + rcc_periph_clock_enable(RCC_USART1); +} + +static void gpio_setup(void) +{ + /* Setup GPIO pin GPIO8/9 on GPIO port C for LEDs. */ + gpio_mode_setup(GPIOC, GPIO_MODE_OUTPUT, GPIO_PUPD_NONE, GPIO8 | GPIO9); + + /* Setup GPIO pins for USART2 transmit. */ + gpio_mode_setup(GPIOA, GPIO_MODE_AF, GPIO_PUPD_NONE, GPIO9); + + /* Setup USART1 TX pin as alternate function. */ + gpio_set_af(GPIOA, GPIO_AF1, GPIO9); +} + +int main(void) +{ + int i, c = 0; + FILE *fp; + + clock_setup(); + gpio_setup(); + fp = usart_setup(USART1); + + /* Blink the LED (PD12) on the board with every transmitted byte. */ + while (1) { + gpio_toggle(GPIOC, GPIO8); /* LED on/off */ + + fprintf(fp,"Pass: %d\n",c); + + c = (c == 200) ? 0 : c + 1; /* Increment c. */ + + for (i = 0; i < 1000000; i++) /* Wait a bit. */ + __asm__("NOP"); + } + + return 0; +}