X09-009PKC-RA Digi International/Maxstream, X09-009PKC-RA Datasheet - Page 46

• Manufacturer Part Number: X09-009PKC-RA
• Description: MOD RF 900MHZ 9600BPS RS232/485
• Manufacturer: Digi International/Maxstream
• Series: XStream™r

Specifications of X09-009PKC-RA

• Function: Transceiver, FHSS
• Modulation Or Protocol: FHSS, FSK
• Frequency: 900MHz
• Applications: ISM
• Interface: RS-232, RS-485
• Sensitivity: -110dBm
• Power - Output: 20dBm (100mW)
• Data Rate - Maximum: 10 kbps
• Voltage - Supply: 7 V ~ 18 V
• Package / Case: Module
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Features: -

© 2006 MaxStream, Inc. Confidential & Proprietary
XStream‐PKG‐R™ RS‐232/485 RF Modem – Product Manual v5.x00 [2006.02.24]
5.3. Acknowledged Communications
5.3.1. Acknowledged Mode
Connection Sequence
Characteristics:
Recommended Use: Acknowledge Mode configuration is appropriate when reliable delivery is
required between modems. If messages are smaller than 256 bytes, use RB and RO commands
to align RF packets with application packets.
Required Parameter Values (TX Modem): RR (Retries) >= 1
Related Commands: Networking (DT, MK, RR), Serial Interfacing (PK, RN, TT, RO, RB)
Table 5.4.
Modem
All
Figure 5.6.
After sending a packet while
in Acknowledged Mode, the
transmitting modem listens
for an ACK
(acknowledgement). If it
receives the ACK, it will either
send a subsequent packet (if
more transmit data is
pending), or will wait for
exactly RN random delay slots
before allowing another
transmission (if no more data
is pending for transmission).
If the transmitting modem
does not receive the ACK
within the allotted time, it will
retransmit the packet with a
new RF initializer following the
ACK slot. There is no delay
between the first ACK slot and
the first retransmission.
Subsequent retransmissions
incur a delay of a random
number of delay slots,
between 0 and RN. If RN is
set to 0 on the transmitting
modem, there are never any
back-off delays between
retransmissions. Note that
during back-off delays, the
transmitting modem will go
into Idle Mode and may
receive RF data. This can h
the effect of increasing the ba
retransmit) mode as long as it is receiving RF data.
Sample Network Profile
Acknowledged Mode State Diagram
Reliable delivery through positive acknowledgements for each packet
Throughput, latency and jitter vary depending on the quality of the channel
and the strength of the signal.
Parameter Settings (assume default values for parameters not listed)
ATRR A
ATRN 5
ave
ck-off delay, as the radio cannot return to RF transmit (or
[set number of Retries to 0x0A]
[set number of Delay Slots to 5]
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