1.. _grow_r502a:
2
3GROW_R502A Fingerprint Sensor
4#############################
5
6Overview
7********
8
9This sample has the below functionalities:
10
11#. Shows the number of fingerprints stored in the sensor.
12#. When SENSOR_ATTR_RECORD_FREE_IDX is set then it search for free index in sensor library.
13#. When SENSOR_ATTR_RECORD_ADD is set then it adds a new fingerprint to the sensor.
14#. When SENSOR_ATTR_RECORD_FIND is set then it tries to find a match for the input fingerprint. On finding a match it returns ID and confidence.
15#. When SENSOR_ATTR_RECORD_DEL is set then it deletes a fingerprint from the sensor.
16
17Note: Fingerprint add & delete functionalities work only when SENSOR_TRIG_TOUCH is set.
18Tricolored LED in the sensor hardware will, flash on the below conditions:
19
20#. On successful addition or deletion of fingerprint it will flash in blue three times.
21#. On finding a match for the input fingerprint it will flash in purple.
22#. In all other cases it will flash in red.
23
24Wiring
25*******
26
27This sample uses an external breakout for the sensor.  A devicetree
28overlay must be provided to identify the UART bus and the GPIO
29used to control the sensor. Sensor can be powered using mentioned optional GPIO.
30
31References
32**********
33
34For more information about the GROW_R502A Fingerprint Sensor see
35http://en.hzgrow.com/product/143.html
36
37Building and Running
38********************
39
40After providing a devicetree overlay that specifies the sensor location,
41build this sample app using:
42
43.. zephyr-app-commands::
44   :zephyr-app: samples/sensor/grow_r502a
45   :board: nrf52840dk_nrf52840
46   :goals: build flash
47
48Sample Output
49*************
50
51.. code-block:: console
52
53    *** Booting Zephyr OS build zephyr-v3.1.0-2640-g328bb73113d4  ***
54    template count : 0
55    Fingerprint Deleted at ID #3
56    Fingerprint template free idx at ID #0
57    Waiting for valid finger to enroll as ID #0
58    Place your finger
59    Fingerprint successfully stored at #0
60    template count : 1
61    Matched ID : 0
62    confidence : 170
63    template count : 1
64    Matched ID : 0
65    confidence : 136
66    template count : 1
67    Matched ID : 0
68    confidence : 318
69    <repeats endlessly>
70