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©
2019 Radiocrafts AS
MBUS User Manual (ver 2.01)
MBUS USER MANUAL
Command
Details
Comments
ASCII
hex
‘P’
0x50
Output Power
This command is used to change the volatile paramter
RF_POWER in RAM.
Argument
Options
Returns
Power Level
1-5
See datasheet for output
power levels.
Prompt (>)
‘Q’
0x51
Quality Indicator
This command returns one byte indicating the signal quality of
the last received packet. It is based on a soft decision signal
quality of the demodulator
Argument
Options
Returns
(none)
(none)
1 byte quality
number
+ Prompt (>)
‘R’
0x52
Read Mailbox
Argument
Options
Returns
Mailbox #
1-16
Mailbox
content
+ Prompt (>)
The mailboxes are
typically used for setting
up automatic two-way
communication. Please
see chapter 7 for details.
Setter function:
•
‘W’-command
‘S’
0x53
Signal Strength (RSSI)
Argument
Options
Returns
(none)
(none)
1 byte quality
number
+ Prompt (>)
The module provide a digital Received Signal Strength Indicator
(RSSI) through the ‘S’ command, or attached to the received
messages (RSSI_MODE configuration parameter). The RSSI
value appended to a received message is the signal strength of
that received packet. The RSSI value is an 8 bit character (one
byte) indicating the current input signal strength or the signal
strength of the received message. The signal strength can be
used as an indication of fading margin, or as a carrier sense
signal to avoid collisions.
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]
The instantaneous RSSI
can be read using the ‘S’
command. This reading
has a delay due to the
settling time of the
receiver.
MBUS4 only:
For continuously
monitoring RSSI, a faster
way is to use
•
‘3’ (Test mode 3) to
set RX mode
•
‘s’ (small caps) to
read the RSSI
multiple times
•
‘4’ (Test mode 4) to
exit RX mode
