OVMS3-idf/components/soc/esp32s2/include/hal/adc_ll.h
2020-01-22 12:14:38 +08:00

611 lines
22 KiB
C

#pragma once
#include "soc/adc_periph.h"
#include "hal/adc_types.h"
#include "soc/apb_ctrl_struct.h"
#include <stdbool.h>
typedef enum {
ADC_DIG_FORMAT_12BIT, /*!< ADC to I2S data format, [15:12]-channel [11:0]-12 bits ADC data.
Note: In single convert mode. */
ADC_DIG_FORMAT_11BIT, /*!< ADC to I2S data format, [15]-1 [14:11]-channel [10:0]-11 bits ADC data.
Note: In multi convert mode. */
ADC_DIG_FORMAT_MAX,
} adc_ll_dig_output_format_t;
typedef enum {
ADC_CONV_SINGLE_UNIT_1 = 1, /*!< SAR ADC 1*/
ADC_CONV_SINGLE_UNIT_2 = 2, /*!< SAR ADC 2, not supported yet*/
ADC_CONV_BOTH_UNIT = 3, /*!< SAR ADC 1 and 2, not supported yet */
ADC_CONV_ALTER_UNIT = 7, /*!< SAR ADC 1 and 2 alternative mode, not supported yet */
ADC_CONV_UNIT_MAX,
} adc_ll_convert_mode_t;
typedef enum {
ADC_NUM_1 = 0, /*!< SAR ADC 1 */
ADC_NUM_2 = 1, /*!< SAR ADC 2 */
ADC_NUM_MAX,
} adc_ll_num_t;
typedef struct {
union {
struct {
uint8_t atten: 2; /*!< ADC sampling voltage attenuation configuration.
0: input voltage * 1;
1: input voltage * 1/1.34;
2: input voltage * 1/2;
3: input voltage * 1/3.6. */
uint8_t bit_width: 2; /*!< ADC resolution.
0: 9 bit;
1: 10 bit;
2: 11 bit;
3: 12 bit. */
uint8_t channel: 4; /*!< ADC channel index. */
};
uint8_t val;
};
} adc_ll_pattern_table_t;
typedef enum {
ADC_POWER_BY_FSM, /*!< ADC XPD controled by FSM. Used for polling mode */
ADC_POWER_SW_ON, /*!< ADC XPD controled by SW. power on. Used for DMA mode */
ADC_POWER_SW_OFF, /*!< ADC XPD controled by SW. power off. */
ADC_POWER_MAX, /*!< For parameter check. */
} adc_ll_power_t;
typedef enum {
ADC_HALL_CTRL_ULP = 0x0,/*!< Hall sensor controled by ULP */
ADC_HALL_CTRL_RTC = 0x1 /*!< Hall sensor controled by RTC */
} adc_ll_hall_controller_t ;
typedef enum {
ADC_CTRL_RTC = 0,
ADC_CTRL_ULP = 1,
ADC_CTRL_DIG = 2,
ADC2_CTRL_PWDET = 3,
} adc_ll_controller_t ;
/*---------------------------------------------------------------
Digital controller setting
---------------------------------------------------------------*/
/**
* Set adc fsm interval parameter for digital controller. These values are fixed for same platforms.
*
* @param rst_wait cycles between DIG ADC controller reset ADC sensor and start ADC sensor.
* @param start_wait Delay time after open xpd.
* @param standby_wait Delay time to close xpd.
*/
static inline void adc_ll_dig_set_fsm_time(uint32_t rst_wait, uint32_t start_wait, uint32_t standby_wait)
{
// Internal FSM reset wait time
APB_CTRL.saradc_fsm_wait.rstb_wait = rst_wait;
// Internal FSM start wait time
APB_CTRL.saradc_fsm_wait.xpd_wait = start_wait;
// Internal FSM standby wait time
APB_CTRL.saradc_fsm_wait.standby_wait = standby_wait;
}
/**
* Set adc sample cycle for digital controller.
*
* @note Normally, please use default value.
* @param sample_cycle Cycles between DIG ADC controller start ADC sensor and beginning to receive data from sensor.
* Range: 2 ~ 0xFF.
*/
static inline void adc_ll_dig_set_sample_cycle(uint32_t sample_cycle)
{
APB_CTRL.saradc_fsm.sample_cycle = sample_cycle;
}
/**
* Set adc output data format for digital controller.
*
* @param format Output data format.
*/
static inline void adc_ll_dig_set_output_format(adc_ll_dig_output_format_t format)
{
APB_CTRL.saradc_ctrl.data_sar_sel = format;
}
/**
* Set adc max conversion number for digital controller.
* If the number of ADC conversion is equal to the maximum, the conversion is stopped.
*
* @param meas_num Max conversion number. Range: 0 ~ 255.
*/
static inline void adc_ll_dig_set_convert_limit_num(uint32_t meas_num)
{
APB_CTRL.saradc_ctrl2.max_meas_num = meas_num;
}
/**
* Enable max conversion number detection for digital controller.
* If the number of ADC conversion is equal to the maximum, the conversion is stopped.
*/
static inline void adc_ll_dig_convert_limit_enable(void)
{
APB_CTRL.saradc_ctrl2.meas_num_limit = 1;
}
/**
* Disable max conversion number detection for digital controller.
* If the number of ADC conversion is equal to the maximum, the conversion is stopped.
*/
static inline void adc_ll_dig_convert_limit_disable(void)
{
APB_CTRL.saradc_ctrl2.meas_num_limit = 0;
}
/**
* Set adc conversion mode for digital controller.
*
* @note ESP32 only support ADC1 single mode.
*
* @param mode Conversion mode select.
*/
static inline void adc_ll_dig_set_convert_mode(adc_ll_convert_mode_t mode)
{
if (mode == ADC_CONV_SINGLE_UNIT_1) {
APB_CTRL.saradc_ctrl.work_mode = 0;
APB_CTRL.saradc_ctrl.sar_sel = 0;
} else if (mode == ADC_CONV_SINGLE_UNIT_2) {
APB_CTRL.saradc_ctrl.work_mode = 0;
APB_CTRL.saradc_ctrl.sar_sel = 1;
} else if (mode == ADC_CONV_BOTH_UNIT) {
APB_CTRL.saradc_ctrl.work_mode = 1;
} else if (mode == ADC_CONV_ALTER_UNIT) {
APB_CTRL.saradc_ctrl.work_mode = 2;
}
}
/**
* Set I2S DMA data source for digital controller.
*
* @param src i2s data source.
*/
static inline void adc_ll_dig_set_data_source(adc_i2s_source_t src)
{
/* 1: I2S input data is from SAR ADC (for DMA) 0: I2S input data is from GPIO matrix */
APB_CTRL.saradc_ctrl.data_to_i2s = src;
}
/**
* Set pattern table lenth for digital controller.
* The pattern table that defines the conversion rules for each SAR ADC. Each table has 16 items, in which channel selection,
* resolution and attenuation are stored. When the conversion is started, the controller reads conversion rules from the
* pattern table one by one. For each controller the scan sequence has at most 16 different rules before repeating itself.
*
* @prarm adc_n ADC unit.
* @param patt_len Items range: 1 ~ 16.
*/
static inline void adc_ll_set_pattern_table_len(adc_ll_num_t adc_n, uint32_t patt_len)
{
if (adc_n == ADC_NUM_1) {
APB_CTRL.saradc_ctrl.sar1_patt_len = patt_len - 1;
} else { // adc_n == ADC_NUM_2
APB_CTRL.saradc_ctrl.sar2_patt_len = patt_len - 1;
}
}
/**
* Set pattern table lenth for digital controller.
* The pattern table that defines the conversion rules for each SAR ADC. Each table has 16 items, in which channel selection,
* resolution and attenuation are stored. When the conversion is started, the controller reads conversion rules from the
* pattern table one by one. For each controller the scan sequence has at most 16 different rules before repeating itself.
*
* @prarm adc_n ADC unit.
* @param pattern_index Items index. Range: 1 ~ 16.
* @param pattern Stored conversion rules.
*/
static inline void adc_ll_set_pattern_table(adc_ll_num_t adc_n, uint32_t pattern_index, adc_ll_pattern_table_t pattern)
{
uint32_t tab;
uint8_t *arg;
if (adc_n == ADC_NUM_1) {
tab = *(uint32_t *)(&APB_CTRL.saradc_sar1_patt_tab1 + pattern_index / 4);
arg = (uint8_t *)&tab;
arg[pattern_index % 4] = pattern.val;
*(uint32_t *)(&APB_CTRL.saradc_sar1_patt_tab1 + pattern_index / 4) = tab;
} else { // adc_n == ADC_NUM_2
tab = *(uint32_t *)(&APB_CTRL.saradc_sar2_patt_tab1 + pattern_index / 4);
arg = (uint8_t *)&tab;
arg[pattern_index % 4] = pattern.val;
*(uint32_t *)(&APB_CTRL.saradc_sar2_patt_tab1 + pattern_index / 4) = tab;
}
}
/*---------------------------------------------------------------
PWDET(Power detect) controller setting
---------------------------------------------------------------*/
/**
* Set adc cct for PWDET controller.
*
* @note Capacitor tuning of the PA power monitor. cct set to the same value with PHY.
* @prarm cct Range: 0 ~ 7.
*/
static inline void adc_ll_pwdet_set_cct(uint32_t cct)
{
/* Capacitor tuning of the PA power monitor. cct set to the same value with PHY. */
SENS.sar_meas2_mux.sar2_pwdet_cct = cct;
}
/**
* Get adc cct for PWDET controller.
*
* @note Capacitor tuning of the PA power monitor. cct set to the same value with PHY.
* @return cct Range: 0 ~ 7.
*/
static inline uint32_t adc_ll_pwdet_get_cct(void)
{
/* Capacitor tuning of the PA power monitor. cct set to the same value with PHY. */
return SENS.sar_meas2_mux.sar2_pwdet_cct;
}
/*---------------------------------------------------------------
RTC controller setting
---------------------------------------------------------------*/
/**
* Set adc output data format for RTC controller.
*
* @prarm adc_n ADC unit.
* @prarm bits Output data bits width option.
*/
static inline void adc_ll_rtc_set_output_format(adc_ll_num_t adc_n, adc_bits_width_t bits)
{
if (adc_n == ADC_NUM_1) {
SENS.sar_meas1_ctrl1.sar1_bit_width = bits;
SENS.sar_reader1_ctrl.sar1_sample_bit = bits;
} else { // adc_n == ADC_NUM_2
SENS.sar_meas2_ctrl1.sar2_bit_width = bits;
SENS.sar_reader2_ctrl.sar2_sample_bit = bits;
}
}
/**
* Enable adc channel to start convert.
*
* @note Only one channel can be selected for once measurement.
*
* @prarm adc_n ADC unit.
* @param channel ADC channel number for each ADCn.
*/
static inline void adc_ll_rtc_enable_channel(adc_ll_num_t adc_n, int channel)
{
if (adc_n == ADC_NUM_1) {
SENS.sar_meas1_ctrl2.sar1_en_pad = (1 << channel); //only one channel is selected.
} else { // adc_n == ADC_NUM_2
SENS.sar_meas2_ctrl2.sar2_en_pad = (1 << channel); //only one channel is selected.
}
}
/**
* Start conversion once by software for RTC controller.
*
* @note It may be block to wait conversion idle for ADC1.
*
* @prarm adc_n ADC unit.
* @param channel ADC channel number for each ADCn.
*/
static inline void adc_ll_rtc_start_convert(adc_ll_num_t adc_n, int channel)
{
if (adc_n == ADC_NUM_1) {
while (SENS.sar_slave_addr1.meas_status != 0);
SENS.sar_meas1_ctrl2.meas1_start_sar = 0;
SENS.sar_meas1_ctrl2.meas1_start_sar = 1;
} else { // adc_n == ADC_NUM_2
SENS.sar_meas2_ctrl2.meas2_start_sar = 0; //start force 0
SENS.sar_meas2_ctrl2.meas2_start_sar = 1; //start force 1
}
}
/**
* Check the conversion done flag for each ADCn for RTC controller.
*
* @prarm adc_n ADC unit.
* @return
* -true : The conversion process is finish.
* -false : The conversion process is not finish.
*/
static inline bool adc_ll_rtc_convert_is_done(adc_ll_num_t adc_n)
{
bool ret = true;
if (adc_n == ADC_NUM_1) {
ret = (bool)SENS.sar_meas1_ctrl2.meas1_done_sar;
} else { // adc_n == ADC_NUM_2
ret = (bool)SENS.sar_meas2_ctrl2.meas2_done_sar;
}
return ret;
}
/**
* Get the converted value for each ADCn for RTC controller.
*
* @prarm adc_n ADC unit.
* @return
* - Converted value.
*/
static inline int adc_ll_rtc_get_convert_value(adc_ll_num_t adc_n)
{
int ret_val = 0;
if (adc_n == ADC_NUM_1) {
ret_val = SENS.sar_meas1_ctrl2.meas1_data_sar;
} else { // adc_n == ADC_NUM_2
ret_val = SENS.sar_meas2_ctrl2.meas2_data_sar;
}
return ret_val;
}
/*---------------------------------------------------------------
Common setting
---------------------------------------------------------------*/
/**
* Set ADC module power management.
*
* @prarm manage Set ADC power status.
*/
static inline void adc_ll_set_power_manage(adc_ll_power_t manage)
{
/* Bit1 0:Fsm 1: SW mode
Bit0 0:SW mode power down 1: SW mode power on */
if (manage == ADC_POWER_SW_ON) {
SENS.sar_power_xpd_sar.force_xpd_sar = SENS_FORCE_XPD_SAR_PU;
} else if (manage == ADC_POWER_BY_FSM) {
SENS.sar_power_xpd_sar.force_xpd_sar = SENS_FORCE_XPD_SAR_FSM;
} else if (manage == ADC_POWER_SW_OFF) {
SENS.sar_power_xpd_sar.force_xpd_sar = SENS_FORCE_XPD_SAR_PD;
}
}
/**
* Get ADC module power management.
*
* @return
* - ADC power status.
*/
static inline adc_ll_power_t adc_ll_get_power_manage(void)
{
/* Bit1 0:Fsm 1: SW mode
Bit0 0:SW mode power down 1: SW mode power on */
adc_ll_power_t manage;
if (SENS.sar_power_xpd_sar.force_xpd_sar == SENS_FORCE_XPD_SAR_PU) {
manage = ADC_POWER_SW_ON;
} else if (SENS.sar_power_xpd_sar.force_xpd_sar == SENS_FORCE_XPD_SAR_PD) {
manage = ADC_POWER_SW_OFF;
} else {
manage = ADC_POWER_BY_FSM;
}
return manage;
}
/**
* ADC module clock division factor setting. ADC clock devided from APB clock.
*
* @prarm div Division factor.
*/
static inline void adc_ll_set_clk_div(uint32_t div)
{
/* ADC clock devided from APB clk, e.g. 80 / 2 = 40Mhz, */
APB_CTRL.saradc_ctrl.sar_clk_div = div;
}
/**
* Set the attenuation of a particular channel on ADCn.
*
* @note For any given channel, this function must be called before the first time conversion.
*
* The default ADC full-scale voltage is 1.1V. To read higher voltages (up to the pin maximum voltage,
* usually 3.3V) requires setting >0dB signal attenuation for that ADC channel.
*
* When VDD_A is 3.3V:
*
* - 0dB attenuaton (ADC_ATTEN_DB_0) gives full-scale voltage 1.1V
* - 2.5dB attenuation (ADC_ATTEN_DB_2_5) gives full-scale voltage 1.5V
* - 6dB attenuation (ADC_ATTEN_DB_6) gives full-scale voltage 2.2V
* - 11dB attenuation (ADC_ATTEN_DB_11) gives full-scale voltage 3.9V (see note below)
*
* @note The full-scale voltage is the voltage corresponding to a maximum reading (depending on ADC1 configured
* bit width, this value is: 4095 for 12-bits, 2047 for 11-bits, 1023 for 10-bits, 511 for 9 bits.)
*
* @note At 11dB attenuation the maximum voltage is limited by VDD_A, not the full scale voltage.
*
* Due to ADC characteristics, most accurate results are obtained within the following approximate voltage ranges:
*
* - 0dB attenuaton (ADC_ATTEN_DB_0) between 100 and 950mV
* - 2.5dB attenuation (ADC_ATTEN_DB_2_5) between 100 and 1250mV
* - 6dB attenuation (ADC_ATTEN_DB_6) between 150 to 1750mV
* - 11dB attenuation (ADC_ATTEN_DB_11) between 150 to 2450mV
*
* For maximum accuracy, use the ADC calibration APIs and measure voltages within these recommended ranges.
*
* @prarm adc_n ADC unit.
* @prarm channel ADCn channel number.
* @prarm atten The attenuation option.
*/
static inline void adc_ll_set_atten(adc_ll_num_t adc_n, adc_channel_t channel, adc_atten_t atten)
{
if (adc_n == ADC_NUM_1) {
SENS.sar_atten1 = ( SENS.sar_atten1 & ~(0x3 << (channel * 2)) ) | ((atten & 0x3) << (channel * 2));
} else { // adc_n == ADC_NUM_2
SENS.sar_atten2 = ( SENS.sar_atten2 & ~(0x3 << (channel * 2)) ) | ((atten & 0x3) << (channel * 2));
}
}
/**
* ADC module output data invert or not.
*
* @prarm adc_n ADC unit.
*/
static inline void adc_ll_output_invert(adc_ll_num_t adc_n, bool inv_en)
{
if (adc_n == ADC_NUM_1) {
SENS.sar_reader1_ctrl.sar1_data_inv = inv_en; // Enable / Disable ADC data invert
} else { // adc_n == ADC_NUM_2
SENS.sar_reader2_ctrl.sar2_data_inv = inv_en; // Enable / Disable ADC data invert
}
}
/**
* Set ADC module controller.
* There are five SAR ADC controllers:
* Two digital controller: Continuous conversion mode (DMA). High performance with multiple channel scan modes;
* Two RTC controller: Single conversion modes (Polling). For low power purpose working during deep sleep;
* the other is dedicated for Power detect (PWDET / PKDET), Only support ADC2.
*
* @prarm adc_n ADC unit.
* @prarm ctrl ADC controller.
*/
static inline void adc_ll_set_controller(adc_ll_num_t adc_n, adc_ll_controller_t ctrl)
{
if (adc_n == ADC_NUM_1) {
switch ( ctrl ) {
case ADC_CTRL_RTC:
SENS.sar_meas1_mux.sar1_dig_force = 0; // 1: Select digital control; 0: Select RTC control.
SENS.sar_meas1_ctrl2.meas1_start_force = 1; // 1: SW control RTC ADC start; 0: ULP control RTC ADC start.
SENS.sar_meas1_ctrl2.sar1_en_pad_force = 1; // 1: SW control RTC ADC bit map; 0: ULP control RTC ADC bit map;
SENS.sar_hall_ctrl.xpd_hall_force = 1; // 1: SW control HALL power; 0: ULP FSM control HALL power.
SENS.sar_hall_ctrl.hall_phase_force = 1; // 1: SW control HALL phase; 0: ULP FSM control HALL phase.
break;
case ADC_CTRL_ULP:
SENS.sar_meas1_mux.sar1_dig_force = 0; // 1: Select digital control; 0: Select RTC control.
SENS.sar_meas1_ctrl2.meas1_start_force = 0; // 1: SW control RTC ADC start; 0: ULP control RTC ADC start.
SENS.sar_meas1_ctrl2.sar1_en_pad_force = 0; // 1: SW control RTC ADC bit map; 0: ULP control RTC ADC bit map;
SENS.sar_hall_ctrl.xpd_hall_force = 0; // 1: SW control HALL power; 0: ULP FSM control HALL power.
SENS.sar_hall_ctrl.hall_phase_force = 0; // 1: SW control HALL phase; 0: ULP FSM control HALL phase.
break;
case ADC_CTRL_DIG:
SENS.sar_meas1_mux.sar1_dig_force = 1; // 1: Select digital control; 0: Select RTC control.
SENS.sar_meas1_ctrl2.meas1_start_force = 1; // 1: SW control RTC ADC start; 0: ULP control RTC ADC start.
SENS.sar_meas1_ctrl2.sar1_en_pad_force = 1; // 1: SW control RTC ADC bit map; 0: ULP control RTC ADC bit map;
SENS.sar_hall_ctrl.xpd_hall_force = 1; // 1: SW control HALL power; 0: ULP FSM control HALL power.
SENS.sar_hall_ctrl.hall_phase_force = 1; // 1: SW control HALL phase; 0: ULP FSM control HALL phase.
break;
default:
break;
}
} else { // adc_n == ADC_NUM_2
switch ( ctrl ) {
case ADC_CTRL_RTC:
SENS.sar_meas2_ctrl2.meas2_start_force = 1; // 1: SW control RTC ADC start; 0: ULP control RTC ADC start.
SENS.sar_meas2_ctrl2.sar2_en_pad_force = 1; // 1: SW control RTC ADC bit map; 0: ULP control RTC ADC bit map;
break;
case ADC_CTRL_ULP:
SENS.sar_meas2_ctrl2.meas2_start_force = 0; // 1: SW control RTC ADC start; 0: ULP control RTC ADC start.
SENS.sar_meas2_ctrl2.sar2_en_pad_force = 0; // 1: SW control RTC ADC bit map; 0: ULP control RTC ADC bit map;
break;
case ADC_CTRL_DIG:
SENS.sar_meas2_ctrl2.meas2_start_force = 1; // 1: SW control RTC ADC start; 0: ULP control RTC ADC start.
SENS.sar_meas2_ctrl2.sar2_en_pad_force = 1; // 1: SW control RTC ADC bit map; 0: ULP control RTC ADC bit map;
break;
case ADC2_CTRL_PWDET: // currently only used by Wi-Fi
SENS.sar_meas2_ctrl2.meas2_start_force = 1; // 1: SW control RTC ADC start; 0: ULP control RTC ADC start.
SENS.sar_meas2_ctrl2.sar2_en_pad_force = 1; // 1: SW control RTC ADC bit map; 0: ULP control RTC ADC bit map;
break;
default:
break;
}
}
}
/**
* Close ADC AMP module if don't use it for power save.
*/
static inline void adc_ll_amp_disable(void)
{
//channel is set in the convert function
SENS.sar_meas1_ctrl1.force_xpd_amp = SENS_FORCE_XPD_AMP_PD;
//disable FSM, it's only used by the LNA.
SENS.sar_amp_ctrl3.amp_rst_fb_fsm = 0;
SENS.sar_amp_ctrl3.amp_short_ref_fsm = 0;
SENS.sar_amp_ctrl3.amp_short_ref_gnd_fsm = 0;
SENS.sar_amp_ctrl1.sar_amp_wait1 = 1;
SENS.sar_amp_ctrl1.sar_amp_wait2 = 1;
SENS.sar_amp_ctrl2.sar_amp_wait3 = 1;
}
/*---------------------------------------------------------------
Hall sensor setting
---------------------------------------------------------------*/
/**
* Enable hall sensor.
*/
static inline void adc_ll_hall_enable(void)
{
SENS.sar_hall_ctrl.xpd_hall = 1;
}
/**
* Disable hall sensor.
*/
static inline void adc_ll_hall_disable(void)
{
SENS.sar_hall_ctrl.xpd_hall = 0;
}
/**
* Reverse phase of hall sensor.
*/
static inline void adc_ll_hall_phase_enable(void)
{
SENS.sar_hall_ctrl.hall_phase = 1;
}
/**
* Don't reverse phase of hall sensor.
*/
static inline void adc_ll_hall_phase_disable(void)
{
SENS.sar_hall_ctrl.hall_phase = 0;
}
/**
* Set hall sensor controller.
*
* @param hall_ctrl Hall controller.
*/
static inline void adc_ll_set_hall_controller(adc_ll_hall_controller_t hall_ctrl)
{
SENS.sar_hall_ctrl.xpd_hall_force = hall_ctrl; // 1: SW control HALL power; 0: ULP FSM control HALL power.
SENS.sar_hall_ctrl.hall_phase_force = hall_ctrl; // 1: SW control HALL phase; 0: ULP FSM control HALL phase.
}
/**
* Output ADC2 reference voltage to gpio 25 or 26 or 27
*
* This function utilizes the testing mux exclusive to ADC 2 to route the
* reference voltage one of ADC2's channels. Supported gpios are gpios
* 25, 26, and 27. This refernce voltage can be manually read from the pin
* and used in the esp_adc_cal component.
*
* @param[in] io GPIO number (gpios 25,26,27 supported)
*
* @return
* - true: v_ref successfully routed to selected gpio
* - false: Unsupported gpio
*/
static inline bool adc_ll_vref_output(int io)
{
int channel;
if (io == 25) {
channel = 8; //Channel 8 bit
} else if (io == 26) {
channel = 9; //Channel 9 bit
} else if (io == 27) {
channel = 7; //Channel 7 bit
} else {
return false;
}
RTCCNTL.bias_conf.dbg_atten = 0; //Check DBG effect outside sleep mode
//set dtest (MUX_SEL : 0 -> RTC; 1-> vdd_sar2)
RTCCNTL.test_mux.dtest_rtc = 1; //Config test mux to route v_ref to ADC2 Channels
//set ent
RTCCNTL.test_mux.ent_rtc = 1;
//set sar2_en_test
SENS.sar_meas2_ctrl1.sar2_en_test = 1;
//set sar2 en force
SENS.sar_meas2_ctrl2.sar2_en_pad_force = 1; //Pad bitmap controlled by SW
//set en_pad for channels 7,8,9 (bits 0x380)
SENS.sar_meas2_ctrl2.sar2_en_pad = 1 << channel;
return true;
}