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
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40
examples/stm32/other/adc_temperature_sensor/adc.c
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@@ -60,27 +60,30 @@ void gpio_setup(void)
void adc_setup(void)
{
int i;
rcc_peripheral_enable_clock(&RCC_APB2ENR, RCC_APB2ENR_ADC1EN);
/* make shure it didnt run during config */
/* Make shure it doesn't run during config. */
adc_off(ADC1);
/* we configure everything for one single conversion */
/* We configure everything for one single conversion. */
adc_disable_scan_mode(ADC1);
adc_set_single_conversion_mode(ADC1);
adc_enable_discontinous_mode_regular(ADC1);
adc_disable_external_trigger_regular(ADC1);
adc_set_right_aligned(ADC1);
/* we want read out the temperature sensor so we have to enable it */
/* We want to read the temperature sensor, so we have to enable it. */
adc_enable_temperature_sensor(ADC1);
adc_set_conversion_time_on_all_channels(ADC1, ADC_SMPR_SMP_28DOT5CYC);
adc_set_conversion_time_on_all_channels(ADC1, ADC_SMPR_SMP_28DOT5CYC);
adc_on(ADC1);
/* wait for adc starting up*/
for (i = 0; i < 80000; i++); /* Wait (needs -O0 CFLAGS). */
/* Wait for ADC starting up. */
for (i = 0; i < 800000; i++) /* Wait a bit. */
__asm__("nop");
adc_reset_calibration(ADC1);
adc_calibration(ADC1);
adc_calibration(ADC1);
}
void my_usart_print_int(u32 usart, int value)
@@ -95,13 +98,12 @@ void my_usart_print_int(u32 usart, int value)
}
while (value > 0) {
buffer[nr_digits++] = "0123456789"[value%10];
value = value/10;
buffer[nr_digits++] = "0123456789"[value % 10];
value /= 10;
}
for (i=nr_digits; i>=0; i--) {
for (i = nr_digits; i >= 0; i--)
usart_send(usart, buffer[i]);
}
}
int main(void)
@@ -124,19 +126,25 @@ int main(void)
usart_send(USART1, '\r');
usart_send(USART1, '\n');
/* Select the channel we want to convert. 16=temperature_sensor */
/* Select the channel we want to convert. 16=temperature_sensor. */
channel_array[0] = 16;
adc_set_regular_sequence(ADC1, 1, channel_array);
/* If the ADC_CR2_ON bit is already set -> setting it another time starts the conversion */
/*
* If the ADC_CR2_ON bit is already set -> setting it another time
* starts the conversion.
*/
adc_on(ADC1);
/* Waiting for end of conversion */
/* Wait for end of conversion. */
while (!(ADC_SR(ADC1) & ADC_SR_EOC));
temperature = ADC_DR(ADC1);
/* thats actually not the real temparature - you have to compute it like described in the datasheet */
/*
* That's actually not the real temperature - you have to compute it
* as described in the datasheet.
*/
my_usart_print_int(USART1, temperature);
gpio_clear(GPIOB, GPIO6); /* LED2 on */