AMIS-49587
http://onsemi.com
4
File Transfer Application
The file transfer application sends a file from the transmitter to
the receiver. Before initiating transmit, the addressed node should
be ready to receive the file. Click on ‘Receive File’ to open a file
save dialog box. Enter the file name. The receiver node is now
waiting for the complete file to arrive. On the transmitter node,
click the ‘Transmit File’ button. A file open dialog box will
appear. Choose the file to be sent. Transmit will start
immediately.
Figure 7 Node transmitting a file
Transmit or receive can be aborted at any time by clicking the
‘Stop’ button.
The file transfer application can be used to implement a BER
test. Bit error rate can be calculated by comparing the received file
with the original (not implemented by this application).
Figure 8 Node receiving a file
Special Scenarios
Repetition with Credit and Time Slot Counter change.
When the configuration for a server is setting the MODEM as a
repeater: set 1,2 or 3 in the Repeater section of the xml
configuration file, the MODEM will repeat messages addressed to
a different MODEM only when the current credit field in the data
frame is higher than 0
…
<Repeater>
<Bits>2</Bits>
<Value>
3
</Value>
<Note>
0 Never Repeater or Mode=Master,
1 Always Repeater,
2 Not Repeater (accept frame ISACall),
3 Repeater (accept frame ISACall)
</Note>
</Repeater>
The time slot counter is communicated to an external processor
or to the GUI by means of the time slot field in the status message.
The time slot counter should be used by the external processor to
block data transmission when repetition is ongoing.
The default value of the time slot counter is 7 (maximum
number of repetitions is 8: from 0 to 7) and indicates that the
communication channel is free for transmission. When the
MODEM is repeating a message, it is decrements it’s time slot
counter every time the MODEM autonomously sends the message
on the power line. At the same time the MODEM decrements the
current credit field in the frame.
This process can be partially visualized using the GUI. 3
MODEMS are needed:
One with master configuration
One with slave configuration
One with Spy configuration
Steps to follow, after all MODEMS have been configured:
1)
Make sure the Spy window is set to logging level 1 and
master to level 3.
2)
Make sure the master/slave are not synchronized
3)
Check the status of both MODEMS and witness that the
time slot counter is in both 7.
4)
Open the chat window in master
5)
Set CC (Current Credit) and IC (Initial Credit) to 2
6)
Set the Address field to an address that is different (!!)
from the slave address
