diff options
| author | Dan Halbert <halbert@halwitz.org> | 2017-12-15 11:40:35 -0500 |
|---|---|---|
| committer | Scott Shawcroft <scott@tannewt.org> | 2017-12-15 09:56:39 -0800 |
| commit | 0c0a09aeb6ec0357acbe64b034c162c805e07c9e (patch) | |
| tree | a2fb8fbf3df6e341eef257f6366dfbecc0fa5451 | |
| parent | 6d603e462d578a83bfeab78bfdf806d8d45c6701 (diff) | |
Speed up AnalogIn.value.
| -rw-r--r-- | atmel-samd/common-hal/analogio/AnalogIn.c | 9 | ||||
| -rw-r--r-- | atmel-samd/common-hal/microcontroller/Processor.c | 4 |
2 files changed, 9 insertions, 4 deletions
diff --git a/atmel-samd/common-hal/analogio/AnalogIn.c b/atmel-samd/common-hal/analogio/AnalogIn.c index 03c502dff..cbb9f5de5 100644 --- a/atmel-samd/common-hal/analogio/AnalogIn.c +++ b/atmel-samd/common-hal/analogio/AnalogIn.c @@ -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) { diff --git a/atmel-samd/common-hal/microcontroller/Processor.c b/atmel-samd/common-hal/microcontroller/Processor.c index c398c5e6f..15bfb510b 100644 --- a/atmel-samd/common-hal/microcontroller/Processor.c +++ b/atmel-samd/common-hal/microcontroller/Processor.c @@ -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; |