Evaluation Kit User Manual
EV9000
2001 Consumer Microcircuits Limited
42
UM9000/2
4.6.7 Test 7: Tx user defined packet from B to A driving PTT & starting acquire on CS
4.6.7.1 Application
Execute a one-way, user configured, packet data transfer from channel B to channel A. PTT is
actively controlled by channel B and channel A starts its receive procedure upon an indication on
the CS input for execution with user provided rf circuits.
This test is different in the ES9690xx.EXE software and is described in Appendix B.
4.6.7.2 Description
This test exercises the two modem channels to execute the transfer of a complete message from
channel B to channel A. The predefined message structure makes use of realistic block types
(e.g. Header, Intermediate, and Last blocks) to expose the transmit parameters and receive
information involved in a message transfer. Transmit parameters are user configurable to support
user designed experiments. In addition, other information such as the state of the data quality
output is observed and recorded during the course of the test. Upon test completion, gathered
data may be saved to disk in a tab-delimited file.
To support ‘live’ system operation with rf transceivers, this test asserts PTT on transmit and uses
CS to trigger the reception process on the receive channel modem. PTT and CS each serve an
important role in most wireless systems: Push To Talk is used to key on a radio transmitter and
Carrier Sense is asserted by a radio receiver to trigger the start of its modem’s receive process.
The test control parameters are provided during test setup to configure timing aspects of the
message transfer. They are described below:
Tx Preamble Length: the length of preamble to be sent by channel B.
Post Tx Length: the amount of time, measured in bit or symbol times, for which PTT will
persist after channel B BFREE status goes high.
Rx Acquire Delay: the amount of time, measured in bit or symbol times, after CS is
recognised until channel A initiates its receive sequence with an SFS task (with AQLEV and
AQBC or AQSC set).
4.6.7.3 Screen Control
Execution of this test involves the following steps:
1.
Click on the
GO
button in the main window. A Message Parameters window is displayed
(see Figures 25 to 30).
2.
Set the desired parameters in the Message Parameters window. Use the pull down lists to
select among different data presentation schemes (hex, ASCII, etc.). Click on the
OK
button
to execute the test and display results. If the test does not seem to be executing
successfully, press the HALT switch to abort the test.
3.
Results may be viewed in the Rx Message Information window which is displayed. Click on
the
OK
button to advance. An alert box provides the option to save results to a tab-delimited
file (default name ES9000.XLT or similar).
4.
After performing the save operation, control is returned to the main window.
Samples of the screen control windows are shown below. For a detailed description of the
various modem parameters, refer to that particular modem’s data sheet.
