sergiotarxz/nuttx
sergiotarxz/nuttx
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

fix: sensor: ppg of dual- and quad-channel sensor types

Browse Source 
Some PPG devices have 4 ADCs to output quad-channel PPG values while some of them only have 2 ADCs to output dual-channel PPG.
To deal the case above, the type PPGD(PPG of Dual-channel) takes the place of former type PPG, which also have 2-channel PPG outputs. Type PPGQ (PPG of Quad-channel) is new for 4-ADC-PPG. Both types have contained new data "gain" to indicate ADC gains of each PPG channel, for the reason that the gains may vary during automatical optical adjustments.

Signed-off-by: liucheng5 <liucheng5@xiaomi.com>
This commit is contained in:
liucheng5 2022-01-06 14:47:53 +08:00 committed by Xiang Xiao
parent b0d24f53c4
commit 764fc7ef5e
2 changed files with 37 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
drivers/sensors/sensor.c
View File

@ -126,7 +126,8 @@ static const struct sensor_info g_sensor_info[] =
{sizeof(struct sensor_event_hrate), "hrate"},
{sizeof(struct sensor_event_hbeat), "hbeat"},
{sizeof(struct sensor_event_ecg), "ecg"},
{sizeof(struct sensor_event_ppg), "ppg"},
{sizeof(struct sensor_event_ppgd), "ppgd"},
{sizeof(struct sensor_event_ppgq), "ppgq"},
{sizeof(struct sensor_event_impd), "impd"},
{sizeof(struct sensor_event_ots), "ots"},
{sizeof(struct sensor_event_gps_satellite), "gps_satellite"},

50
include/nuttx/sensors/sensor.h
View File

@ -226,17 +226,27 @@
#define SENSOR_TYPE_ECG 25
/* PPG (Photoplethysmography)
* A sensor of this type returns the PPG measurements in counts. The PPG
* measurements come from photodiode and following current amplifiers, where
* the photodiode switches reflected light intensity to current. Here the PPG
* value means the ADC counts, since the LED lightness, the photodiode model,
* the reflect-ratio, and the integration time of ADC varies with different
* measurements, while the useful information of PPG is the not the magnitude
* but the shape of the waveform.
/* PPG Dual (2-channel photoplethysmography)
* A sensor of this type returns the 2 channels PPG measurements in ADC
* counts and their corresponding LED current and ADC gains. The PPG
* measurements come from photodiodes and following current amplifiers and
* ADCs, where a photodiode switches reflected light intensity to current.
* The LED current decides the lightness of LED, which is the input of PPG
* measurements. The ADC gains are multipled on the output and affect SNR.
*/
#define SENSOR_TYPE_PPG 26
#define SENSOR_TYPE_PPGD 26
/* PPG Quad (4-channel photoplethysmography)
* A sensor of this type returns the 4 channels PPG measurements in ADC
* counts and their corresponding LED current and ADC gains. The PPG
* measurements come from photodiodes and following current amplifiers and
* ADCs, where a photodiode switches reflected light intensity to current.
* The LED current decides the lightness of LED, which is the input of PPG
* measurements. The ADC gains are multipled on the output and affect SNR.
*/
#define SENSOR_TYPE_PPGQ 27
/* Imdepance
* A sensor of this type returns the impedance measurements. An impedance
@ -244,7 +254,7 @@
* imaginary part(reactance). Both of them are in uint Ohm(Ω).
*/
#define SENSOR_TYPE_IMPEDANCE 27
#define SENSOR_TYPE_IMPEDANCE 28
/* OTS (Optical tracking sensor)
* A sensor of this type returns the OTS measurements in counts. It
@ -253,17 +263,17 @@
* design flexibility into a compact device.
*/
#define SENSOR_TYPE_OTS 28
#define SENSOR_TYPE_OTS 29
/* Sensor of gps satellite
* A sensor of this type returns the gps satellite information.
*/
#define SENSOR_TYPE_GPS_SATELLITE 29
#define SENSOR_TYPE_GPS_SATELLITE 30
/* The total number of sensor */
#define SENSOR_TYPE_COUNT 30
#define SENSOR_TYPE_COUNT 31
/****************************************************************************
* Inline Functions
@ -480,10 +490,20 @@ struct sensor_event_ecg /* Type: ECG */
float ecg; /* Unit is μV */
};
struct sensor_event_ppg /* Type: PPG */
struct sensor_event_ppgd /* Type: PPGD */
{
uint64_t timestamp; /* Unit is microseconds */
uint32_t ppg; /* Unit is ADC counts */
uint32_t ppg[2]; /* PPG from 2 channels. Units are ADC counts. */
uint32_t current; /* LED current. Unit is uA. */
uint16_t gain[2]; /* ADC gains of channels. Units are V/V or V/A. */
};
struct sensor_event_ppgq /* Type: PPDQ */
{
uint64_t timestamp; /* Unit is microseconds */
uint32_t ppg[4]; /* PPG from 4 channels. Units are ADC counts. */
uint32_t current; /* LED current. Unit is uA. */
uint16_t gain[4]; /* ADC gains of channels. Units are V/V or V/A. */
};
struct sensor_event_impd /* Type: Impedance */