From 66fd5373b4d1f99d2b34b7223c8964e3cb70de9f Mon Sep 17 00:00:00 2001 From: Piotr Esden-Tempski Date: Wed, 29 Dec 2010 05:39:25 +0100 Subject: Implemented a uart example that is using irq for receive and transmit. --- examples/obldc/usart_irq/Makefile | 24 +++++++ examples/obldc/usart_irq/usart_irq.c | 126 ++++++++++++++++++++++++++++++++++ examples/obldc/usart_irq/usart_irq.ld | 31 +++++++++ 3 files changed, 181 insertions(+) create mode 100644 examples/obldc/usart_irq/Makefile create mode 100644 examples/obldc/usart_irq/usart_irq.c create mode 100644 examples/obldc/usart_irq/usart_irq.ld (limited to 'examples') diff --git a/examples/obldc/usart_irq/Makefile b/examples/obldc/usart_irq/Makefile new file mode 100644 index 0000000..1c0a6c2 --- /dev/null +++ b/examples/obldc/usart_irq/Makefile @@ -0,0 +1,24 @@ +## +## This file is part of the libopenstm32 project. +## +## Copyright (C) 2009 Uwe Hermann +## +## 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 3 of the License, or +## (at your option) 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. +## +## You should have received a copy of the GNU General Public License +## along with this program. If not, see . +## + +BINARY = usart_irq + +OOCD_BOARD = open-bldc + +include ../../Makefile.include diff --git a/examples/obldc/usart_irq/usart_irq.c b/examples/obldc/usart_irq/usart_irq.c new file mode 100644 index 0000000..5be24d2 --- /dev/null +++ b/examples/obldc/usart_irq/usart_irq.c @@ -0,0 +1,126 @@ +/* + * This file is part of the libopenstm32 project. + * + * Copyright (C) 2009 Uwe Hermann + * + * 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 3 of the License, or + * (at your option) 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. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ + +#include +#include +#include +#include + +void clock_setup(void) +{ + rcc_clock_setup_in_hse_8mhz_out_72mhz(); + + /* Enable GPIOA clock. For LED gpio's */ + rcc_peripheral_enable_clock(&RCC_APB2ENR, RCC_APB2ENR_IOPAEN); + + /* Enable clocks for GPIO port B (for GPIO_USART1_TX) 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) +{ + + /* Enable the USART1 interrupt. */ + nvic_enable_irq(NVIC_USART1_IRQ); + + /* enable USART1 pin software remapping */ + AFIO_MAPR |= AFIO_MAPR_USART1_REMAP; + + /* Setup GPIO pin GPIO_USART1_RE_TX 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 GPIO pin GPIO_USART1_RE_RX on GPIO port B for receive. */ + gpio_set_mode(GPIOB, GPIO_MODE_INPUT, + GPIO_CNF_INPUT_FLOAT, GPIO_USART1_RE_RX); + + /* Setup UART parameters. */ + usart_set_baudrate(USART1, 230400); + usart_set_databits(USART1, 8); + usart_set_stopbits(USART1, USART_STOPBITS_1); + usart_set_parity(USART1, USART_PARITY_NONE); + usart_set_flow_control(USART1, USART_FLOWCONTROL_NONE); + usart_set_mode(USART1, USART_MODE_TX_RX); + + /* Enable USART1 Receive interrupt. */ + USART_CR1(USART1) |= USART_CR1_RXNEIE; + + /* Finally enable the USART. */ + usart_enable(USART1); +} + +void gpio_setup(void) +{ + + gpio_set(GPIOA, GPIO6 | GPIO7); + + /* Setup GPIO6 and 7 (in GPIO port A) for led use. */ + gpio_set_mode(GPIOA, GPIO_MODE_OUTPUT_50_MHZ, + GPIO_CNF_OUTPUT_PUSHPULL, + GPIO6 | GPIO7); + +} + +void usart1_isr(void) +{ + static u8 data = 'A'; + + /* Check if we were called because of RXNE. */ + if ((USART_SR(USART1) & USART_SR_RXNE) != 0) { + + /* Indicate that we got data. */ + gpio_toggle(GPIOA, GPIO6); + + /* Retrieve the data from the peripheral. */ + data = usart_recv(USART1); + + /* Enable transmit interrupt so it sends back the data. */ + USART_CR1(USART1) |= USART_CR1_TXEIE; + } + + /* Check if we were called because of TXE. */ + if ((USART_SR(USART1) & USART_SR_TXE) != 0) { + + /* Indicate that we are sending out data. */ + gpio_toggle(GPIOA, GPIO7); + + /* Put data into the transmit register */ + usart_send(USART1, data); + + /* Disable the TXE interrupt as we don't need it anymore */ + USART_CR1(USART1) &= ~USART_CR1_TXEIE; + } +} + +int main(void) +{ + + clock_setup(); + gpio_setup(); + usart_setup(); + + /* Wait forever and do nothing. */ + while (1) { + __asm("nop"); + } + + return 0; +} diff --git a/examples/obldc/usart_irq/usart_irq.ld b/examples/obldc/usart_irq/usart_irq.ld new file mode 100644 index 0000000..c8683d5 --- /dev/null +++ b/examples/obldc/usart_irq/usart_irq.ld @@ -0,0 +1,31 @@ +/* + * This file is part of the libopenstm32 project. + * + * Copyright (C) 2009 Uwe Hermann + * + * 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 3 of the License, or + * (at your option) 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. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ + +/* Linker script for Open-BLDC (STM32F103CBT6, 128K flash, 20K RAM). */ + +/* Define memory regions. */ +MEMORY +{ + rom (rx) : ORIGIN = 0x08000000, LENGTH = 128K + ram (rwx) : ORIGIN = 0x20000000, LENGTH = 20K +} + +/* Include the common ld script from libopenstm32. */ +INCLUDE libopenstm32.ld + -- cgit v1.2.3