User's Manual

MaxStream 9XStream™ Wireless OEM Module Manual v2.8
32
Confidential and Proprietary, ©MaxStream, Inc. 2001
Experiment 1 – Byte Transmission (cont.)
From Figures A1 and A2, it is evident that the sync timer
parameter can save significant amounts of time by reducing the
header length.
As shown in Figure A1, the first byte, which included
synchronization information in the header, was sent and
received in 41.4 ms. Once the modules were synchronized, the
second byte transmission did not have the synchronization
information included in the header. This transmission occurred
in only 10.0 ms – a savings of about 75%. This is shown on
similar testing on the 9600-baud modules showed 48.4 ms to
transmit the first byte and synchronize the modules, and 16.2
ms to transmit the second byte without synchronization
information. This experiment was followed by a second test to
note the effect of the sync timer command on transmitting a
continuous data stream.
Experiment 2 – Data Transmission
A continuous stream of 32 byte packets was sent to the
9XStream transmitter through a serial connection and then
transmitted to a 9XStream receiver located several feet away.
This experiment was performed using 19200-baud modules.
The transmission time was first measured with the modules in
their default condition, and then measured again after setting
the sync timer (SY command) to 20. The following output plots
were obtained from an oscilloscope. (Again, the signal at the
transmitter is shown in yellow, while the receiver's signal is
shown in blue.)
Figure B1 – Oscilloscope output of transmitted and received
data under normal conditions.