From 4837775449d531b4eaaf1ab86653757f8906238e Mon Sep 17 00:00:00 2001 From: Chuck McManis Date: Mon, 16 Feb 2015 20:52:00 -0800 Subject: [PATCH] Nucleo F411RE - Simple USART example Same as the one for other boards --- .../stm32/f4/nucleo-f411re/usart/Makefile | 26 ++++++ .../stm32/f4/nucleo-f411re/usart/README.md | 21 +++++ examples/stm32/f4/nucleo-f411re/usart/usart.c | 84 +++++++++++++++++++ 3 files changed, 131 insertions(+) create mode 100644 examples/stm32/f4/nucleo-f411re/usart/Makefile create mode 100644 examples/stm32/f4/nucleo-f411re/usart/README.md create mode 100644 examples/stm32/f4/nucleo-f411re/usart/usart.c diff --git a/examples/stm32/f4/nucleo-f411re/usart/Makefile b/examples/stm32/f4/nucleo-f411re/usart/Makefile new file mode 100644 index 0000000..7e8b080 --- /dev/null +++ b/examples/stm32/f4/nucleo-f411re/usart/Makefile @@ -0,0 +1,26 @@ +## +## This file is part of the libopencm3 project. +## +## Copyright (C) 2009 Uwe Hermann +## Copyright (C) 2015 Chuck McManis +## +## 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 = ../nucleo-f411re.ld + +include ../../Makefile.include + diff --git a/examples/stm32/f4/nucleo-f411re/usart/README.md b/examples/stm32/f4/nucleo-f411re/usart/README.md new file mode 100644 index 0000000..a0b9c8e --- /dev/null +++ b/examples/stm32/f4/nucleo-f411re/usart/README.md @@ -0,0 +1,21 @@ +# README + +This example program sends repeating sequence of characters "0123456789" on +USART2 on the ST Nucleo F411RE eval board. + +The sending is done in a blocking way. + +Note that the Nucleo board exports the serial port as an ttyACM device on +Linux or a COM port on Windows. On Linux, if you can locate the correct +serial port as + +/dev/serial/by-id/usb-STMicroelectronics_STM32_STLink_066CFF515056805087171825-if02 + +(note there will be differences based on the serial number of your board) +this may also show up as /dev/ttyACM0 if it was the first serial port +enumerated, if you have additional serial devices attached to the USB port +of your system they may show up as additional ttyACM1/ttyACM2/... etc. + +Connect to the port using `screen /dev/ttyACM0 115200` where you replace +the serial port with the one for your system. + diff --git a/examples/stm32/f4/nucleo-f411re/usart/usart.c b/examples/stm32/f4/nucleo-f411re/usart/usart.c new file mode 100644 index 0000000..b4ee7b1 --- /dev/null +++ b/examples/stm32/f4/nucleo-f411re/usart/usart.c @@ -0,0 +1,84 @@ +/* + * This file is part of the libopencm3 project. + * + * Copyright (C) 2009 Uwe Hermann + * Copyright (C) 2011 Stephen Caudle + * Copyright (C) 2015 Chuck McManis + * + * 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 + +static void clock_setup(void) +{ + /* Enable GPIOD clock for LED & USARTs. */ + rcc_periph_clock_enable(RCC_GPIOA); + + /* Enable clocks for USART2. */ + rcc_periph_clock_enable(RCC_USART2); +} + +static void usart_setup(void) +{ + /* Setup USART2 parameters. */ + usart_set_baudrate(USART2, 115200); + usart_set_databits(USART2, 8); + usart_set_stopbits(USART2, USART_STOPBITS_1); + usart_set_mode(USART2, USART_MODE_TX); + usart_set_parity(USART2, USART_PARITY_NONE); + usart_set_flow_control(USART2, USART_FLOWCONTROL_NONE); + + /* Finally enable the USART. */ + usart_enable(USART2); +} + +static void gpio_setup(void) +{ + /* Setup GPIO pin GPIO5 on GPIO port A for LED. */ + gpio_mode_setup(GPIOA, GPIO_MODE_OUTPUT, GPIO_PUPD_NONE, GPIO5); + + /* Setup GPIO pins for USART2 transmit. */ + gpio_mode_setup(GPIOA, GPIO_MODE_AF, GPIO_PUPD_NONE, GPIO2); + + /* Setup USART2 TX pin as alternate function. */ + gpio_set_af(GPIOA, GPIO_AF7, GPIO2); +} + +int main(void) +{ + int i, j = 0, c = 0; + + clock_setup(); + gpio_setup(); + usart_setup(); + + /* Blink the LED (PD12) on the board with every transmitted byte. */ + while (1) { + gpio_toggle(GPIOA, GPIO5); /* LED on/off */ + usart_send_blocking(USART2, c + '0'); /* USART2: Send byte. */ + c = (c == 9) ? 0 : c + 1; /* Increment c. */ + if ((j++ % 80) == 0) { /* Newline after line full. */ + usart_send_blocking(USART2, '\r'); + usart_send_blocking(USART2, '\n'); + } + for (i = 0; i < 300000; i++) { /* Wait a bit. */ + __asm__("NOP"); + } + } + + return 0; +}