Rainbow Electronics RC1180-MBUS - Manual (Page 14)

RC1180-MBUS
 2008 Radiocrafts AS RC1180-MBUS Data Sheet (rev. 1.0) Page 14 of 28
RSSI Reading
The module provide a digital Received Signal Strength Indicator (RSSI) through the ‘S’
command, or attached to received messages. The module returns an 8 bit character (one
byte) indicating the current input signal strength (followed immediately by a second character
which is the prompt (‘>’) when in command mode). The signal strength can be used as an
indication of fading margin, or as a carrier sense signal to avoid collisions.
The signal strength measure by the S command is the instantaneous value. The RSSI value
appended to a received message (RSSI_MODE = 1) is the signal strength of that received
packet.
The RSSI value increases with increased input signal strength in 0.5 dB steps. Input signal
strength is given by (typ.):
P = - RSSI / 2 [dBm]