XBIB-R Digi International/Maxstream, XBIB-R Datasheet - Page 50

• Manufacturer Part Number: XBIB-R
• Description: BOARD RS232 ZIGBEE MOD PRO
• Manufacturer: Digi International/Maxstream

Specifications of XBIB-R

• Design Resources: XBIB-R Schematic
• Accessory Type: Interface Board
• For Use With/related Products: XBee and XBee Pro Radios
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

XBee/XBee‐PRO™ OEM RF Modules ‐ 802.15.4 ‐ v1.xAx [2007.05.031]
RO (Packetization Timeout) Command
RP (RSSI PWM Timer) Command
RR (XBee Retries) Command
<Serial Interfacing> RO command is used to set
and read the number of character times of inter-
character delay required before transmission.
RF transmission commences when data is
detected in the DI (data in from host) buffer and
RO character times of silence are detected on the
UART receive lines (after receiving at least 1 byte).
RF transmission will also commence after 100 Bytes (maximum packet size) are received in the DI
buffer.
Set the RO parameter to '0' to transmit characters as they arrive instead of buffering them into
one RF packet.
<I/O Settings {I/O Line Passing}> The RP com-
mand is used to enable PWM (Pulse Width Modu-
lation) output on the RF module. The output is
calibrated to show the level a received RF signal is
above the sensitivity level of the module. The
PWM pulses vary from 24 to 100%. Zero percent
means PWM output is inactive. One to 24% per-
cent means the received RF signal is at or below the published sensitivity level of the module. The
following table shows levels above sensitivity and PWM values.
The total period of the PWM output is 64 µs. Because there are 445 steps in the PWM output, the
minimum step size is 144 ns.
PWM Percentages
A non-zero value defines the time that the PWM output will be active with the RSSI value of the
last received RF packet. After the set time when no RF packets are received, the PWM output will
be set low (0 percent PWM) until another RF packet is received. The PWM output will also be set
low at power-up until the first RF packet is received. A parameter value of 0xFF permanently
enables the PWM output and it will always reflect the value of the last received RF packet.
<Networking {Addressing}> The RR command is
used set/read the maximum number of retries
the module will execute in addition to the 3
retries provided by the 802.15.4 MAC. For each
XBee retry, the 802.15.4 MAC can execute up to 3
retries.
This values does not need to be set on all modules for retries to work. If retries are enabled, the
transmitting module will set a bit in the Maxstream RF Packet header which requests the receiving
module to send an ACK (acknowledgement). If the transmitting module does not receive an ACK
within 200 msec, it will re-send the packet within a random period up to 48 msec. Each XBee retry
can potentially result in the MAC sending the packet 4 times (1 try plus 3 retries). Note that retries
are not attempted for packets that are purged when transmitting with a Cyclic Sleep Coordinator.
© 2007 MaxStream, Inc.
dB above Sensitivity
10
20
30
(high period / total period)
PWM percentage
41%
58%
75%
AT Command: ATRO
Parameter Range:0 - 0xFF
Default Parameter Value: 3
AT Command: ATRP
Parameter Range:0 - 0xFF
Default Parameter Value: 0x28 (40 decimal)
AT Command: ATRR
Parameter Range: 0 - 6
Default: 0
Minimum Firmware Version Required: 1.xA0
Chapter 3 ‐ RF Module Configuration
[x character times]
[x 100 msec]
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