Functions to support testing the RSSI of the FlexSense. More...

Macros
#define	FLEX_RSSI_DEFAULT_FREQUENCY_HZ 400500000
	The default frequency, in Hertz, used for executing the RSSI test.

Functions
bool	FLEX_RSSICalcSupport (void)

int32_t	FLEX_RSSIAvgCalcRun (const uint32_t start_delay_ms, const uint32_t frequency_hz, const uint32_t samples_count, const uint32_t read_interval_ms, const bool should_log)

Detailed Description

Functions to support testing the RSSI of the FlexSense.

RSSI testing

The FlexSense Received Signal Strength Indicator (RSSI) testing functions are disabled by default. To enable them, you must include the flag -Drssi_calc_support=true when building. The complete meson command for setup will look like this:

meson setup –crossfile flex-crossfile.ini -Drssi_calc_support=true build

Impacts of Enabling RSSI Testing

BLE Advertisements: FlexSense will no longer automatically enable BLE Advertisements on startup.
Manual Activation: The physical button on the unit will still start the BLE advertisement.
RSSI Readings: FlexSense will no longer perform its own RSSI reading test. You must implement the readings yourself if you want a value reported via the FlexAssist application.

Important Note on Accuracy

Be aware that BLE advertising will cause inaccurate RSSI readings. It is critical to design your applications to minimize or avoid concurrent BLE advertising during RSSI measurements.

Function Documentation

◆ FLEX_RSSICalcSupport()

bool FLEX_RSSICalcSupport ( void )

Reports whether the user application was compiled with the option -Drssi_calc_support=true.

◆ FLEX_RSSIAvgCalcRun()

int32_t FLEX_RSSIAvgCalcRun	(	const uint32_t	start_delay_ms,
		const uint32_t	frequency_hz,
		const uint32_t	samples_count,
		const uint32_t	read_interval_ms,
		const bool	should_log )

This function performs a series of Received Signal Strength Indicator (RSSI) readings and returns their average.

Parameters

start_delay_ms	The time, in milliseconds, to wait before the first reading. This delay can help prevent inaccurate measurements caused by the proximity of the tester's body to the device before testing begins.
frequency_hz	The frequency, in hertz, at which to test for RSSI. This should almost always be set to `FLEX_RSSI_DEFAULT_FREQUENCY_HZ`.
samples_count	The total number of RSSI samples to be read.
read_interval_ms	The delay, in milliseconds, between each consecutive RSSI reading.
should_log	A boolean flag indicating whether the RSSI readings should be logged. The logs are viewable in the DeviceAssist logs window.

Returns: The cacluated RSSI average

Return values

0	This most likely indicates that application was not built with `-Drssi_calc_support=true`. You should check the result of `bool FLEX_RSSICalcSupport(void)`
< -99	Indicates a "good" noise level
-99 to -95	Indicates a "acceptable" noise level
>= -94	Indicates a "poor" noise level

Macros