ZAURA Datasheet, PDF (22/99 Pages) –

ZAURA RF Wireless Library
Programmer’s Reference Manual
10
SDATA. Used to transmit application data using the ZAURA RF Reliable
Data Transfer and Flow Control (RDTFC) protocol (reliable data trans-
mission).
ACK. Used by the RDTFC to acknowledge receipt of an SDATA frame
The SAP field can be used to segregate application data into different log-
ical streams. See the Service Access Points section on page 11 for more
information.
The DA_SA_CTRL format is shown in Figure 3.
PA(2) NID(1–4) Len(1)
DA(1)
SA(1)
CTRL(1) Data(58) CRC(2)
Figure 3. Fields within the DA_SA_CTRL Frame
This DA_SA_CTRL frame format must be used to enable ZAURA RF
reliable data services. The ZAURA RF Wireless Library is configured to
use this frame format by default.
Limitations and Utility of the DA_SA_CTRL Format. The DA_SA_CTRL
format allows the transmitter to determine if the intended recipient of a
packet actually received the data that was sent. This frame format also
allows a simple point-to-point flow control mechanism to be implemented
through the use of ACK frames.
When this frame format is used, the effective application data rate will
typically be lower than that of the other frame formats because of a longer
header as well as software overhead incurred with the operation of the
reliable data transfer protocol.
This frame format is most useful in applications where it is more impor-
tant to know whether a frame was successfully received than to transmit
data as fast as possible.
The ZAURA RF Wireless Library
RM006003-1011