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Speed up AnalogIn.value.

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This commit is contained in:
Dan Halbert 2017-12-15 11:40:35 -05:00 committed by Scott Shawcroft
parent 6d603e462d
commit 0c0a09aeb6
2 changed files with 9 additions and 4 deletions
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9
atmel-samd/common-hal/analogio/AnalogIn.c
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@ -74,8 +74,10 @@ uint16_t common_hal_analogio_analogin_get_value(analogio_analogin_obj_t *self) {
config_adc.reference = ADC_REFERENCE_INTVCC1;
config_adc.gain_factor = ADC_GAIN_FACTOR_DIV2;
config_adc.positive_input = self->pin->adc_input;
config_adc.resolution = ADC_RESOLUTION_16BIT;
config_adc.clock_prescaler = ADC_CLOCK_PRESCALER_DIV128;
config_adc.resolution = ADC_RESOLUTION_12BIT;
// Default input clock is GCLK0 (48 MHz)
// 48Mhz / 32 = 1.5MHz. Max ADC clock is 2.1MHz
config_adc.clock_prescaler = ADC_CLOCK_PRESCALER_DIV32;
struct adc_module adc_instance;
// ADC must have been disabled before adc_init() is called.
@ -108,7 +110,8 @@ uint16_t common_hal_analogio_analogin_get_value(analogio_analogin_obj_t *self) {
}
adc_disable(&adc_instance);
return data;
// Scale to 16 bits. In the future we might make this be this be under API control.
return data * 16;
}
float common_hal_analogio_analogin_get_reference_voltage(analogio_analogin_obj_t *self) {

4
atmel-samd/common-hal/microcontroller/Processor.c
View File

@ -111,7 +111,9 @@ STATIC void configure_adc_temp(struct adc_module *adc_instance) {
// "Discard the first conversion result whenever there is a change
// in ADC configuration like voltage reference / ADC channel change."
config_adc.clock_prescaler = ADC_CLOCK_PRESCALER_DIV16;
// Default input clock is GCLK0 (48 MHz)
// 48Mhz / 32 = 1.5MHz. Max ADC clock is 2.1MHz
config_adc.clock_prescaler = ADC_CLOCK_PRESCALER_DIV32;
config_adc.reference = ADC_REFERENCE_INT1V;
config_adc.positive_input = ADC_POSITIVE_INPUT_TEMP;
config_adc.negative_input = ADC_NEGATIVE_INPUT_GND;