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Diffstat (limited to 'examples/stm32/f1/stm32-h103/usart_irq_printf/usart_irq_printf.c')
-rw-r--r--examples/stm32/f1/stm32-h103/usart_irq_printf/usart_irq_printf.c136
1 files changed, 66 insertions, 70 deletions
diff --git a/examples/stm32/f1/stm32-h103/usart_irq_printf/usart_irq_printf.c b/examples/stm32/f1/stm32-h103/usart_irq_printf/usart_irq_printf.c
index deee527..35503c8 100644
--- a/examples/stm32/f1/stm32-h103/usart_irq_printf/usart_irq_printf.c
+++ b/examples/stm32/f1/stm32-h103/usart_irq_printf/usart_irq_printf.c
@@ -2,7 +2,7 @@
* This file is part of the libopencm3 project.
*
* Copyright (C) 2009 Uwe Hermann <uwe@hermann-uwe.de>,
- * 2011 Piotr Esden-Tempski <piotr@esden.net>
+ * Copyright (C) 2011 Piotr Esden-Tempski <piotr@esden.net>
*
* 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
@@ -23,7 +23,6 @@
#include <libopencm3/stm32/usart.h>
#include <libopencm3/stm32/nvic.h>
#include <libopencm3/stm32/systick.h>
-
#include <stdio.h>
#include <errno.h>
@@ -31,83 +30,81 @@
* Simple ringbuffer implementation from open-bldc's libgovernor that
* you can find at:
* https://github.com/open-bldc/open-bldc/tree/master/source/libgovernor
- ******************************************************************************/
+ *****************************************************************************/
typedef s32 ring_size_t;
struct ring {
- u8 *data;
- ring_size_t size;
- u32 begin;
- u32 end;
+ u8 *data;
+ ring_size_t size;
+ u32 begin;
+ u32 end;
};
-#define RING_SIZE(RING) ((RING)->size - 1)
-#define RING_DATA(RING) (RING)->data
+#define RING_SIZE(RING) ((RING)->size - 1)
+#define RING_DATA(RING) (RING)->data
#define RING_EMPTY(RING) ((RING)->begin == (RING)->end)
-void ring_init(struct ring *ring, u8 * buf, ring_size_t size)
+void ring_init(struct ring *ring, u8 *buf, ring_size_t size)
{
- ring->data = buf;
- ring->size = size;
- ring->begin = 0;
- ring->end = 0;
+ ring->data = buf;
+ ring->size = size;
+ ring->begin = 0;
+ ring->end = 0;
}
s32 ring_write_ch(struct ring *ring, u8 ch)
{
- if (((ring->end + 1) % ring->size) != ring->begin) {
- ring->data[ring->end++] = ch;
- ring->end %= ring->size;
- return (u32) ch;
- }
+ if (((ring->end + 1) % ring->size) != ring->begin) {
+ ring->data[ring->end++] = ch;
+ ring->end %= ring->size;
+ return (u32)ch;
+ }
- return -1;
+ return -1;
}
-s32 ring_write(struct ring * ring, u8 * data, ring_size_t size)
+s32 ring_write(struct ring *ring, u8 *data, ring_size_t size)
{
- s32 i;
+ s32 i;
- for (i = 0; i < size; i++) {
- if (ring_write_ch(ring, data[i]) < 0) {
- return -i;
- }
- }
+ for (i = 0; i < size; i++) {
+ if (ring_write_ch(ring, data[i]) < 0)
+ return -i;
+ }
- return i;
+ return i;
}
-s32 ring_read_ch(struct ring * ring, u8 * ch)
+s32 ring_read_ch(struct ring *ring, u8 *ch)
{
- s32 ret = -1;
+ s32 ret = -1;
- if (ring->begin != ring->end) {
- ret = ring->data[ring->begin++];
- ring->begin %= ring->size;
- if (ch)
- *ch = ret;
- }
+ if (ring->begin != ring->end) {
+ ret = ring->data[ring->begin++];
+ ring->begin %= ring->size;
+ if (ch)
+ *ch = ret;
+ }
- return ret;
+ return ret;
}
-s32 ring_read(struct ring * ring, u8 * data, ring_size_t size)
+s32 ring_read(struct ring *ring, u8 *data, ring_size_t size)
{
- s32 i;
+ s32 i;
- for (i = 0; i < size; i++) {
- if (ring_read_ch(ring, data + i) < 0) {
- return i;
- }
- }
+ for (i = 0; i < size; i++) {
+ if (ring_read_ch(ring, data + i) < 0)
+ return i;
+ }
- return -i;
+ return -i;
}
/******************************************************************************
* The example implementation
- ******************************************************************************/
+ *****************************************************************************/
#define BUFFER_SIZE 1024
@@ -123,14 +120,12 @@ void clock_setup(void)
/* Enable clocks for GPIO port A (for GPIO_USART1_TX) and USART1. */
rcc_peripheral_enable_clock(&RCC_APB2ENR, RCC_APB2ENR_IOPAEN |
- RCC_APB2ENR_AFIOEN |
- RCC_APB2ENR_USART1EN);
+ RCC_APB2ENR_AFIOEN | RCC_APB2ENR_USART1EN);
}
void usart_setup(void)
{
-
- /* Initialize output ring buffer */
+ /* Initialize output ring buffer. */
ring_init(&output_ring, output_ring_buffer, BUFFER_SIZE);
/* Enable the USART1 interrupt. */
@@ -138,7 +133,7 @@ void usart_setup(void)
/* Setup GPIO pin GPIO_USART1_RE_TX on GPIO port B for transmit. */
gpio_set_mode(GPIOA, GPIO_MODE_OUTPUT_50_MHZ,
- GPIO_CNF_OUTPUT_ALTFN_PUSHPULL, GPIO_USART1_TX);
+ GPIO_CNF_OUTPUT_ALTFN_PUSHPULL, GPIO_USART1_TX);
/* Setup GPIO pin GPIO_USART1_RE_RX on GPIO port B for receive. */
gpio_set_mode(GPIOA, GPIO_MODE_INPUT,
@@ -172,7 +167,7 @@ void usart1_isr(void)
{
/* Check if we were called because of RXNE. */
if (((USART_CR1(USART1) & USART_CR1_RXNEIE) != 0) &&
- ((USART_SR(USART1) & USART_SR_RXNE) != 0)) {
+ ((USART_SR(USART1) & USART_SR_RXNE) != 0)) {
/* Indicate that we got data. */
gpio_toggle(GPIOC, GPIO12);
@@ -186,14 +181,14 @@ void usart1_isr(void)
/* Check if we were called because of TXE. */
if (((USART_CR1(USART1) & USART_CR1_TXEIE) != 0) &&
- ((USART_SR(USART1) & USART_SR_TXE) != 0)) {
+ ((USART_SR(USART1) & USART_SR_TXE) != 0)) {
s32 data;
data = ring_read_ch(&output_ring, NULL);
if (data == -1) {
- /* Disable the TXE interrupt as we don't need it anymore. */
+ /* Disable the TXE interrupt, it's no longer needed. */
USART_CR1(USART1) &= ~USART_CR1_TXEIE;
} else {
/* Put data into the transmit register. */
@@ -202,27 +197,28 @@ void usart1_isr(void)
}
}
-int _write (int file, char *ptr, int len)
+int _write(int file, char *ptr, int len)
{
int ret;
if (file == 1) {
ret = ring_write(&output_ring, (u8 *)ptr, len);
- if (ret < 0) ret = -ret;
+ if (ret < 0)
+ ret = -ret;
USART_CR1(USART1) |= USART_CR1_TXEIE;
return ret;
}
- errno = EIO;
- return -1;
+ errno = EIO;
+ return -1;
}
-void systick_setup(void) {
-
- /* 72MHz / 8 => 9000000 counts per second */
+void systick_setup(void)
+{
+ /* 72MHz / 8 => 9000000 counts per second. */
systick_set_clocksource(STK_CTRL_CLKSOURCE_AHB_DIV8);
/* 9000000/9000 = 1000 overflows per second - every 1ms one interrupt */
@@ -232,7 +228,6 @@ void systick_setup(void) {
/* Start counting. */
systick_counter_enable();
-
}
void sys_tick_handler(void)
@@ -240,17 +235,20 @@ void sys_tick_handler(void)
static int counter = 0;
static float fcounter = 0.0;
static double dcounter = 0.0;
-
static u32 temp32 = 0;
temp32++;
- /* We call this handler every 1ms so we are sending hello world every 10ms / 100Hz. */
+ /*
+ * We call this handler every 1ms so we are sending hello world
+ * every 10ms / 100Hz.
+ */
if (temp32 == 10) {
- printf("Hello World! %i %f %f\r\n", counter, fcounter, dcounter);
+ printf("Hello World! %i %f %f\r\n", counter, fcounter,
+ dcounter);
counter++;
- fcounter+=0.01;
- dcounter+=0.01;
+ fcounter += 0.01;
+ dcounter += 0.01;
temp32 = 0;
}
@@ -258,15 +256,13 @@ void sys_tick_handler(void)
int main(void)
{
-
clock_setup();
gpio_setup();
usart_setup();
systick_setup();
- while (1) {
+ while (1)
__asm__("nop");
- }
return 0;
}