Command descriptions
9XTend-PKG-R RS-232/485 RF Modem User Guide
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1 or 2 stop bits [as determined by SB (Stop Bits) Command]
RP (RSSI PWM Timer) Command
<Diagnostics> RP Command is used to enable a PWM ("Pulse Width Modulation") output on the Config/RSSI pin (pin
11 of the OEM RF Module). The pin is calibrated to show the difference between received signal strength and the
sensitivity level of the RF modem. PWM pulses vary from zero to 95 percent. Zero percent means the received RF signal
is at or below the published sensitivity level of the modem.
The following table shows dB levels above sensitivity and PWM values (The total time period of the PWM output is 8.32
ms. PWM output consists of 40 steps and therefore the minimum step size is 0.208 ms.):
A non-zero value defines the time that PWM output is active with the RSSI value of the last received RF packet. After
the set time when no RF packets are received, PWM output is set low (0 percent PWM) until another RF packet is
received. PWM output is also set low at power-up. A parameter value of 0xFF permanently enables PWM output and
always reflects the value of the last received RF packet.
The Config/RSSI pin is shared between PWM output and Config input. When the modem is powered, the Config pin is
an input. During the power-up sequence, if RP parameter is a non-zero value, the Config pin is configured as an output
and set low until the first RF packet is received. With a non-zero RP parameter, the Config pin is an input for RP ms
after power up.
RR (Retries) Command
<Networking and Security> The RR command is used to set/read the maximum number of retries sent for a given RF
packet. When RR Command is enabled (RR>0), RF packet retries and ACKs (acknowledgments) are enabled.
AT Command: ATRO
Binary Command: 0x21 (33 decimal)
Parameter Range:0 - 0xFFFF [ x UART character times ]
Default Parameter Value: 3
Number of bytes returned: 2
Related Commands: RB (Packetization Threshold)
AT Command: ATRP
Binary Command: 0x22 (34 decimal)
Parameter Range:0 - 0xFF [x 100 milliseconds]
Default Parameter Value: 0x20 (32d)
Number of bytes returned: 1
dBm above sensitivity
PWM percentage (high period / total period)
10
20%
20
35%
30
50%