From 956b1dbce4084e4787189e5f812b90e891ef9b7e Mon Sep 17 00:00:00 2001 From: Piotr Esden-Tempski Date: Mon, 12 Nov 2012 14:11:10 -0800 Subject: [examples] Added usart example for obldc strip. --- examples/stm32/f1/obldc-strip/usart/Makefile | 25 ++++++++ examples/stm32/f1/obldc-strip/usart/usart.c | 87 ++++++++++++++++++++++++++++ 2 files changed, 112 insertions(+) create mode 100644 examples/stm32/f1/obldc-strip/usart/Makefile create mode 100644 examples/stm32/f1/obldc-strip/usart/usart.c diff --git a/examples/stm32/f1/obldc-strip/usart/Makefile b/examples/stm32/f1/obldc-strip/usart/Makefile new file mode 100644 index 0000000..40dec09 --- /dev/null +++ b/examples/stm32/f1/obldc-strip/usart/Makefile @@ -0,0 +1,25 @@ +## +## 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 + +LDSCRIPT = ../obldc-strip.ld + +include ../../Makefile.include + diff --git a/examples/stm32/f1/obldc-strip/usart/usart.c b/examples/stm32/f1/obldc-strip/usart/usart.c new file mode 100644 index 0000000..56940e2 --- /dev/null +++ b/examples/stm32/f1/obldc-strip/usart/usart.c @@ -0,0 +1,87 @@ +/* + * This file is part of the libopencm3 project. + * + * Copyright (C) 2012 Piotr Esden-Tempski + * + * 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 + +void clock_setup(void) +{ + rcc_clock_setup_in_hsi_out_64mhz(); + + /* Enable clocks for GPIO port B (for GPIO_USART1_TX and LED) and USART1. */ + rcc_peripheral_enable_clock(&RCC_APB2ENR, RCC_APB2ENR_IOPBEN); + rcc_peripheral_enable_clock(&RCC_APB2ENR, RCC_APB2ENR_AFIOEN); + rcc_peripheral_enable_clock(&RCC_APB2ENR, RCC_APB2ENR_USART1EN); +} + +void usart_setup(void) +{ + /* Setup GPIO6 (in GPIO port A) to 'output push-pull' for LED use. */ + gpio_set_mode(GPIOB, GPIO_MODE_OUTPUT_50_MHZ, + GPIO_CNF_OUTPUT_PUSHPULL, GPIO5); + + AFIO_MAPR |= AFIO_MAPR_USART1_REMAP; + + /* Setup GPIO pin GPIO_USART3_TX/GPIO10 on GPIO port B for transmit. */ + gpio_set_mode(GPIOB, GPIO_MODE_OUTPUT_50_MHZ, + GPIO_CNF_OUTPUT_ALTFN_PUSHPULL, GPIO_USART1_RE_TX); + + /* Setup UART parameters. */ + usart_set_baudrate(USART1, 230400); + usart_set_databits(USART1, 8); + usart_set_stopbits(USART1, USART_STOPBITS_1); + usart_set_mode(USART1, USART_MODE_TX); + usart_set_parity(USART1, USART_PARITY_NONE); + usart_set_flow_control(USART1, USART_FLOWCONTROL_NONE); + + /* Finally enable the USART. */ + usart_enable(USART1); +} + +void gpio_setup(void) +{ + /* Set GPIO5 (in GPIO port B) to 'output push-pull'. */ + gpio_set_mode(GPIOB, GPIO_MODE_OUTPUT_50_MHZ, + GPIO_CNF_OUTPUT_PUSHPULL, GPIO5); +} + +int main(void) +{ + int i, j = 0, c = 0; + + clock_setup(); + gpio_setup(); + usart_setup(); + + /* Blink the LED (PA6) on the board with every transmitted byte. */ + while (1) { + gpio_toggle(GPIOB, GPIO5); /* LED red on/off */ + usart_send_blocking(USART1, c + '0'); /* Send a byte. */ + c = (c == 9) ? 0 : c + 1; /* Increment c. */ + if ((j++ % 80) == 0) { /* Newline after line full. */ + usart_send_blocking(USART1, '\r'); + usart_send_blocking(USART1, '\n'); + } + for (i = 0; i < 800000; i++) /* Wait a bit. */ + __asm__("nop"); + } + + return 0; +} -- cgit v1.2.3