ALS Command

Tag 0x50-0x5f command for ambient light sensor(ALS), used to detect light intensity.

Keyword

NA: Not applicable, this command should no be sent by the sensor/application.

None: No data contained in this command, data length can be set as 0x00.

Tag 0x50

Meaning:
Configure and start ALS with parameters. Use this command before getting data from the ALS.

Data format - app send:

Byte Length 1 2 1 4
Meaning A Time W Time A Gain GA

A Time: ALS integration time. Options refer to code below.
W Time: ALS wait time, time between each integration. Options refer to code below.
A Gain: Gain of the output data, used at low light intensity environment. Options refer to code below.
GA: Glass attenuation. Used to compensate for attenuation, for a device in open air with no aperture or glass/plastic above the device, GA = 1. This is a float number.

One measurement cycle ~= (A Time + W Time)

Data will not stream to the application automatically, command tag 0x52 need to be used to get the ALS illuminance data.

A Time A Time Code W Time W Time Code A Gain A Gain Code
50ms 0xee 0ms 0xffff x0.16 0x04
100ms 0xdb 10ms 0x00fc x1 0x00
150ms 0xc9 20ms 0x00f9 x8 0x01
200ms 0xb7 50ms 0x00ee x16 0x02
250ms 0xa4 100ms 0x00db x120 0x03
300ms 0x92 200ms 0x00b7
350ms 0x80 500ms 0x0049
400ms 0x6d 1000ms 0x01e1
450ms 0x5b 2000ms 0x01c3
500ms 0x49 5000ms 0x0167
550ms 0x37
600ms 0x24
650ms 0x12
700ms 0x00

Data format - app receive:
Same as send format.

Same format will acknowledge to the user after command is executed.

Tag 0x51

Meaning:
Stop and power down ALS. This command will also execute by the sensor when disconnected.

Data format - app send:
None

Data format - app receive:
Same as send format.

Same format will acknowledge to the user after command is executed.

Tag 0x52

Meaning:
Get/reply ALS illuminance data, in unit of lux.

Data format - app send:
None

Data format - app receive:

Byte Length 4
Meaning Lux

The returned lux is a float value.