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-rw-r--r--watch-library/watch/watch_adc.c179
1 files changed, 0 insertions, 179 deletions
diff --git a/watch-library/watch/watch_adc.c b/watch-library/watch/watch_adc.c
deleted file mode 100644
index 5ba7abdf..00000000
--- a/watch-library/watch/watch_adc.c
+++ /dev/null
@@ -1,179 +0,0 @@
-/*
- * MIT License
- *
- * Copyright (c) 2020 Joey Castillo
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-#include "watch_adc.h"
-
-static void _watch_sync_adc(void) {
- while (ADC->SYNCBUSY.reg);
-}
-
-static uint16_t _watch_get_analog_value(uint16_t channel) {
- if (ADC->INPUTCTRL.bit.MUXPOS != channel) {
- ADC->INPUTCTRL.bit.MUXPOS = channel;
- _watch_sync_adc();
- }
-
- ADC->SWTRIG.bit.START = 1;
- while (!ADC->INTFLAG.bit.RESRDY);
-
- return ADC->RESULT.reg;
-}
-
-void watch_enable_adc(void) {
- MCLK->APBCMASK.reg |= MCLK_APBCMASK_ADC;
- GCLK->PCHCTRL[ADC_GCLK_ID].reg = GCLK_PCHCTRL_GEN_GCLK0 | GCLK_PCHCTRL_CHEN;
-
- uint16_t calib_reg = 0;
- calib_reg = ADC_CALIB_BIASREFBUF((*(uint32_t *)ADC_FUSES_BIASREFBUF_ADDR >> ADC_FUSES_BIASREFBUF_Pos)) |
- ADC_CALIB_BIASCOMP((*(uint32_t *)ADC_FUSES_BIASCOMP_ADDR >> ADC_FUSES_BIASCOMP_Pos));
-
- if (!ADC->SYNCBUSY.bit.SWRST) {
- if (ADC->CTRLA.bit.ENABLE) {
- ADC->CTRLA.bit.ENABLE = 0;
- _watch_sync_adc();
- }
- ADC->CTRLA.bit.SWRST = 1;
- }
- _watch_sync_adc();
-
- if (USB->DEVICE.CTRLA.bit.ENABLE) {
- // if USB is enabled, we are running an 8 MHz clock.
- // divide by 16 for a 500kHz ADC clock.
- ADC->CTRLB.bit.PRESCALER = ADC_CTRLB_PRESCALER_DIV16_Val;
- } else {
- // otherwise it's 4 Mhz. divide by 8 for a 500kHz ADC clock.
- ADC->CTRLB.bit.PRESCALER = ADC_CTRLB_PRESCALER_DIV8_Val;
- }
- ADC->CALIB.reg = calib_reg;
- ADC->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_INTVCC2_Val;
- ADC->INPUTCTRL.bit.MUXNEG = ADC_INPUTCTRL_MUXNEG_GND_Val;
- ADC->CTRLC.bit.RESSEL = ADC_CTRLC_RESSEL_16BIT_Val;
- ADC->AVGCTRL.bit.SAMPLENUM = ADC_AVGCTRL_SAMPLENUM_16_Val;
- ADC->SAMPCTRL.bit.SAMPLEN = 0;
- ADC->INTENSET.reg = ADC_INTENSET_RESRDY;
- ADC->CTRLA.bit.ENABLE = 1;
- _watch_sync_adc();
- // throw away one measurement after reference change (the channel doesn't matter).
- _watch_get_analog_value(ADC_INPUTCTRL_MUXPOS_SCALEDCOREVCC);
-}
-
-void watch_enable_analog_input(const uint8_t pin) {
- gpio_set_pin_direction(pin, GPIO_DIRECTION_OFF);
- switch (pin) {
- case A0:
- gpio_set_pin_function(pin, PINMUX_PB04B_ADC_AIN12);
- break;
- case A1:
- gpio_set_pin_function(pin, PINMUX_PB01B_ADC_AIN9);
- break;
- case A2:
- gpio_set_pin_function(pin, PINMUX_PB02B_ADC_AIN10);
- break;
- case A3:
- gpio_set_pin_function(pin, PINMUX_PB03B_ADC_AIN11);
- break;
- case A4:
- gpio_set_pin_function(pin, PINMUX_PB00B_ADC_AIN8);
- break;
- default:
- return;
- }
-}
-
-uint16_t watch_get_analog_pin_level(const uint8_t pin) {
- switch (pin) {
- case A0:
- return _watch_get_analog_value(ADC_INPUTCTRL_MUXPOS_AIN12_Val);
- case A1:
- return _watch_get_analog_value(ADC_INPUTCTRL_MUXPOS_AIN9_Val);
- case A2:
- return _watch_get_analog_value(ADC_INPUTCTRL_MUXPOS_AIN10_Val);
- case A3:
- return _watch_get_analog_value(ADC_INPUTCTRL_MUXPOS_AIN11_Val);
- case A4:
- return _watch_get_analog_value(ADC_INPUTCTRL_MUXPOS_AIN8_Val);
- default:
- return 0;
- }
-}
-
-void watch_set_analog_num_samples(uint16_t samples) {
- // ignore any input that's not a power of 2 (i.e. only one bit set)
- if (__builtin_popcount(samples) != 1) return;
- // if only one bit is set, counting the trailing zeroes is equivalent to log2(samples)
- uint8_t sample_val = __builtin_ctz(samples);
- // make sure the desired value is within range and set it, if so.
- if (sample_val <= ADC_AVGCTRL_SAMPLENUM_1024_Val) {
- ADC->AVGCTRL.bit.SAMPLENUM = sample_val;
- _watch_sync_adc();
- }
-}
-
-void watch_set_analog_sampling_length(uint8_t cycles) {
- // for clarity the API asks the user how many cycles they want the measurement to take.
- // but the ADC always needs at least one cycle; it just wants to know how many *extra* cycles we want.
- // so we subtract one from the user-provided value, and clamp to the maximum.
- ADC->SAMPCTRL.bit.SAMPLEN = (cycles - 1) & 0x3F;
- _watch_sync_adc();
-}
-
-void watch_set_analog_reference_voltage(watch_adc_reference_voltage reference) {
- ADC->CTRLA.bit.ENABLE = 0;
-
- if (reference == ADC_REFERENCE_INTREF) SUPC->VREF.bit.VREFOE = 1;
- else SUPC->VREF.bit.VREFOE = 0;
-
- ADC->REFCTRL.bit.REFSEL = reference;
- ADC->CTRLA.bit.ENABLE = 1;
- _watch_sync_adc();
- // throw away one measurement after reference change (the channel doesn't matter).
- _watch_get_analog_value(ADC_INPUTCTRL_MUXPOS_SCALEDCOREVCC);
-}
-
-uint16_t watch_get_vcc_voltage(void) {
- // stash the previous reference so we can restore it when we're done.
- uint8_t oldref = ADC->REFCTRL.bit.REFSEL;
-
- // if we weren't already using the internal reference voltage, select it now.
- if (oldref != ADC_REFERENCE_INTREF) watch_set_analog_reference_voltage(ADC_REFERENCE_INTREF);
-
- // get the data
- uint32_t raw_val = _watch_get_analog_value(ADC_INPUTCTRL_MUXPOS_SCALEDIOVCC_Val);
-
- // restore the old reference, if needed.
- if (oldref != ADC_REFERENCE_INTREF) watch_set_analog_reference_voltage(oldref);
-
- return (uint16_t)((raw_val * 1000) / (1024 * 1 << ADC->AVGCTRL.bit.SAMPLENUM));
-}
-
-inline void watch_disable_analog_input(const uint8_t pin) {
- gpio_set_pin_function(pin, GPIO_PIN_FUNCTION_OFF);
-}
-
-inline void watch_disable_adc(void) {
- ADC->CTRLA.bit.ENABLE = 0;
- _watch_sync_adc();
-
- MCLK->APBCMASK.reg &= ~MCLK_APBCMASK_ADC;
-}
generated by cgit v1.2.3 (git 2.25.1) at 2025-01-08 10:15:11 +0000