Enable nvic and exti support for L1

And include an example that uses it.
2012-10-22 23:32:42 +00:00
parent b860504fed
commit ce8f47e7df
12 changed files with 215 additions and 197 deletions
--- a/examples/stm32/l1/stm32l-discovery/button-irq-printf/main.c
+++ b/examples/stm32/l1/stm32l-discovery/button-irq-printf/main.c
@@ -0,0 +1,117 @@
+/*
+ * Karl Palsson, 2012 <karlp@tweak.net.au
+ */
+
+#include <errno.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <libopencm3/cm3/nvic.h>
+#include <libopencm3/stm32/l1/rcc.h>
+#include <libopencm3/stm32/l1/gpio.h>
+#include <libopencm3/stm32/exti.h>
+#include <libopencm3/stm32/usart.h>
+
+#include "syscfg.h"
+
+static struct state_t state;
+
+void clock_setup(void) {
+    /* Lots of things on all ports... */
+    rcc_peripheral_enable_clock(&RCC_AHBENR, RCC_AHBENR_GPIOAEN);
+    rcc_peripheral_enable_clock(&RCC_AHBENR, RCC_AHBENR_GPIOBEN);
+
+    /* Enable clocks for USART2. */
+    rcc_peripheral_enable_clock(&RCC_APB1ENR, RCC_APB1ENR_USART2EN);
+}
+
+void gpio_setup(void) {
+    gpio_mode_setup(LED_DISCO_GREEN_PORT, GPIO_MODE_OUTPUT, GPIO_PUPD_NONE, LED_DISCO_GREEN_PIN);
+
+    /* 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);
+}
+
+void usart_setup(void) {
+    usart_set_baudrate(USART_CONSOLE, 115200);
+    usart_set_databits(USART_CONSOLE, 8);
+    usart_set_stopbits(USART_CONSOLE, USART_STOPBITS_1);
+    usart_set_mode(USART_CONSOLE, USART_MODE_TX);
+    usart_set_parity(USART_CONSOLE, USART_PARITY_NONE);
+    usart_set_flow_control(USART_CONSOLE, USART_FLOWCONTROL_NONE);
+
+    /* Finally enable the USART. */
+    usart_enable(USART_CONSOLE);
+}
+
+/**
+ * Use USART_CONSOLE as a console.
+ * @param file
+ * @param ptr
+ * @param len
+ * @return
+ */
+int _write(int file, char *ptr, int len) {
+    int i;
+
+    if (file == STDOUT_FILENO || file == STDERR_FILENO) {
+        for (i = 0; i < len; i++) {
+            if (ptr[i] == '\n') {
+                usart_send_blocking(USART_CONSOLE, '\r');
+            }
+            usart_send_blocking(USART_CONSOLE, ptr[i]);
+        }
+        return i;
+    }
+    errno = EIO;
+    return -1;
+}
+
+void BUTTON_DISCO_USER_isr(void) {
+    exti_reset_request(BUTTON_DISCO_USER_EXTI);
+    if (state.falling) {
+        state.falling = false;
+        exti_set_trigger(BUTTON_DISCO_USER_EXTI, EXTI_TRIGGER_RISING);
+        //        ILOG("fell: %d\n", TIM_CNT(TIM7));
+        puts("fell!\n");
+    } else {
+        puts("Rose!\n");
+        //        TIM_CNT(TIM7) = 0;
+        state.falling = true;
+        exti_set_trigger(BUTTON_DISCO_USER_EXTI, EXTI_TRIGGER_FALLING);
+    }
+}
+
+void setup_buttons(void) {
+    /* Enable EXTI0 interrupt. */
+    nvic_enable_irq(BUTTON_DISCO_USER_NVIC);
+
+    gpio_mode_setup(BUTTON_DISCO_USER_PORT, GPIO_MODE_INPUT, GPIO_PUPD_NONE, BUTTON_DISCO_USER_PIN);
+
+    /* Configure the EXTI subsystem. */
+    exti_select_source(BUTTON_DISCO_USER_EXTI, BUTTON_DISCO_USER_PORT);
+    state.falling = false;
+    exti_set_trigger(BUTTON_DISCO_USER_EXTI, EXTI_TRIGGER_RISING);
+    exti_enable_request(BUTTON_DISCO_USER_EXTI);
+}
+
+int main(void) {
+    int i;
+    int j = 0;
+    clock_setup();
+    gpio_setup();
+    usart_setup();
+    puts("hi guys!\n");
+    setup_buttons();
+    while (1) {
+        puts("tick:");
+        putchar('a' + (j++ % 26));
+        gpio_toggle(GPIOB, GPIO7); /* LED on/off */
+        for (i = 0; i < 100000; i++) /* Wait a bit. */
+            __asm__("NOP");
+    }
+
+    return 0;
+}