User's Manual

Start signal Command | 0x80 Length Status CS

0x02 0x8F 0x01 0x00 0x8C

Status:

0x00: wake-up successful

7.3.6 CMD_RSSI_REQ

This command returns the RX level of the last received packet determined by the transceiver

IC in the form of a signed two’s complement. The current RSSI value of the radio IC ("live

RSSI value") cannot be requested by means of this command.

Format:

Start signal Command Length CS

0x02 0x0D 0x00 0x0F

Response (

CMD_RSSI_CNF

Start signal Command | 0x40 Length RX level CS

0x02 0x4D 0x01 1 Byte 1 Byte

The value obtained in this way delivers the RX level RSSI

dBm

in dBm as follows.

Example: Conversion of the hexadecimal value in two’s complement notation to a decimal

RSSI

dec

0xDB

hex

= 10111101

bin

⇒

−128 + 0 × 64 + 1 × 32 + 1 × 16 + 1 × 8 + 1 × 4 + 0 × 2 + 1 × 1 = −67dBm

If the RSSI equals 0x80 (-128dBm), there is no RSSI value available yet.