From bcce98da54b047a15ef0abf41e0c7794f29f0439 Mon Sep 17 00:00:00 2001 From: Uwe Hermann Date: Thu, 30 Dec 2010 01:52:44 +0100 Subject: Move STM32 examples to examples/stm32 subdir. --- examples/stm32/obldc/systick/systick.c | 90 ++++++++++++++++++++++++++++++++++ 1 file changed, 90 insertions(+) create mode 100644 examples/stm32/obldc/systick/systick.c (limited to 'examples/stm32/obldc/systick/systick.c') diff --git a/examples/stm32/obldc/systick/systick.c b/examples/stm32/obldc/systick/systick.c new file mode 100644 index 0000000..c469c1c --- /dev/null +++ b/examples/stm32/obldc/systick/systick.c @@ -0,0 +1,90 @@ +/* + * This file is part of the libopenstm32 project. + * + * Copyright (C) 2010 Thomas Otto + * Copyright (C) 2010 Piotr Esden-Tempski + * + * 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 +#include + +u32 temp32; + +void gpio_setup(void) +{ + /* Enable GPIOA clock. */ + rcc_peripheral_enable_clock(&RCC_APB2ENR, RCC_APB2ENR_IOPAEN); + + /* Enable GPIOB clock. */ + rcc_peripheral_enable_clock(&RCC_APB2ENR, RCC_APB2ENR_IOPBEN); + + gpio_set(GPIOA, GPIO6); /* LED0 off */ + gpio_set(GPIOA, GPIO7); /* LED1 off */ + gpio_set(GPIOB, GPIO0); /* LED2 off */ + gpio_set(GPIOB, GPIO1); /* LED3 off */ + + /* Set GPIO6/7 (in GPIO port A) to 'output push-pull' for the LEDs. */ + gpio_set_mode(GPIOA, GPIO_MODE_OUTPUT_50_MHZ, + GPIO_CNF_OUTPUT_PUSHPULL, GPIO6); + gpio_set_mode(GPIOA, GPIO_MODE_OUTPUT_50_MHZ, + GPIO_CNF_OUTPUT_PUSHPULL, GPIO7); + + /* Set GPIO6/7 (in GPIO port B) to 'output push-pull' for the LEDs. */ + gpio_set_mode(GPIOB, GPIO_MODE_OUTPUT_50_MHZ, + GPIO_CNF_OUTPUT_PUSHPULL, GPIO0); + gpio_set_mode(GPIOB, GPIO_MODE_OUTPUT_50_MHZ, + GPIO_CNF_OUTPUT_PUSHPULL, GPIO1); +} + +void sys_tick_handler(void) +{ + temp32++; + + /* We call this handler every 1ms so 1000ms = 1s on/off. */ + if (temp32 == 1000) { + gpio_toggle(GPIOA, GPIO6); /* LED2 on/off */ + temp32 = 0; + } +} + +int main(void) +{ + rcc_clock_setup_in_hse_8mhz_out_72mhz(); + gpio_setup(); + + gpio_clear(GPIOA, GPIO7); /* LED1 on */ + gpio_set(GPIOA, GPIO6); /* LED2 off */ + + temp32 = 0; + + /* 72MHz / 8 => 9000000 counts per second */ + systick_set_clocksource(STK_CTRL_CLKSOURCE_AHB_DIV8); + + /* 9000000/9000 = 1000 overflows per second - every 1ms one interrupt */ + systick_set_reload(9000); + + systick_interrupt_enable(); + + /* Start counting. */ + systick_counter_enable(); + + while (1); /* Halt. */ + + return 0; +} -- cgit v1.2.3