EMTime/libopencm3
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Use __asm__("nop") in the loop-based delays.

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Since we recently switched from -O0 to -Os, an increase in the loop count
as well as the addition of __asm__("nop") is required (so that the loop
doesn't get optimized/removed).
The real fix is to add a proper timer-based delay function, of course.

Also, fix a bunch of cosmetic issues and typos.
This commit is contained in:
Uwe Hermann
2011-01-03 01:12:07 +01:00
parent 05f66cde4c
commit ca53311bfc
11 changed files with 82 additions and 61 deletions
Download Patch File Download Diff File Expand all files Collapse all files

20
examples/stm32/obldc/usart_irq/usart_irq.c
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@@ -26,7 +26,7 @@ void clock_setup(void)
{
rcc_clock_setup_in_hse_8mhz_out_72mhz();
/* Enable GPIOA clock. For LED gpio's */
/* Enable GPIOA clock (for LED GPIOs). */
rcc_peripheral_enable_clock(&RCC_APB2ENR, RCC_APB2ENR_IOPAEN);
/* Enable clocks for GPIO port B (for GPIO_USART1_TX) and USART1. */
@@ -37,7 +37,6 @@ void clock_setup(void)
void usart_setup(void)
{
/* Enable the USART1 interrupt. */
nvic_enable_irq(NVIC_USART1_IRQ);
@@ -69,14 +68,11 @@ void usart_setup(void)
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);
GPIO_CNF_OUTPUT_PUSHPULL, GPIO6 | GPIO7);
}
void usart1_isr(void)
@@ -85,7 +81,6 @@ void usart1_isr(void)
/* 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);
@@ -98,29 +93,26 @@ void usart1_isr(void)
/* 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 */
/* Put data into the transmit register. */
usart_send(USART1, data);
/* Disable the TXE interrupt as we don't need it anymore */
/* 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");
}
while (1)
__asm__("nop");
return 0;
}