ZAURA Datasheet, PDF (51/99 Pages) –

ZAURA RF Wireless Library
Programmer’s Reference Manual
39
ZAURA_RF_ReadRSSI
Description This function stores the current Receive Signal Strength Indicator
(RSSI) in the ZAURA_RF_RSSI global variable and returns the value
of the global variable to the caller. The RSSI value returned is an 8-bit
quantity that can range from 0x00 to 0xFF. Typically, the RSSI value
varies over a narrower range.
Note: RSSI can only be sampled if the radio is in the ZAURA_RF_RECEIVE
state. If the radio is not in the ZAURA_RF_RECEIVE state when this
function is called, a value of 0xFF is returned.
The RSSI can be used as a relative indicator of the amount of RF
energy the receiver is detecting. A higher value indicates the presence
of more energy (i.e., close to the transmitter) and a lower value indi-
cates only the presence of noise (no signal being transmitted). The
RSSI value returned can be passed to the ZAURA_RF_Rssi2Pwr
function to estimate the signal strength in dBm.
Because the ZAURA RF Wireless Library can optionally be config-
ured to perform carrier sensing (via RSSI sampling) prior to transmit-
ting data frames, there is typically no need for the application to call
this function before calling the ZAURA_RF_Transmit routine. This
function is most useful while scanning ZAURA RF channels to deter-
mine which channels are in use.
Syntax
UINT8 ZAURA_RF_ReadRSSI( void );
Parameters None.
Returns The current RSSI value.
See Also ZAURA_RF_Rssi2Pwr, ZAURA_RF_GetState,
ZAURA_RF_SetState
Example
UINT8 CurRssi;
RM006003-1011
ZAURA_RF_ReadRSSI