Software Switching To Command Mode; Switching To Data Mode - Javad UHFSSRx User Manual

• A command followed by "/F" option displays the Parameters in the predefined frame format. The display
frame format is unique for each command supporting "/F" option.
Error Code
0x01
0x02
0x03
0x04
0x05

Software Switching to Command Mode

On power-up the radio modem is in data-mode. To switch to command mode the special byte-sequences with
special meanings are used:
• Escape-Sequence: "+++" with 20 ms guard time before and after the command characters
• Escape-Acknowledge: "@00<CR><LF>"
20 ms toggling on CTS control line needed to acknowledge switching from Data to Command mode and vice
versa.
Happy Flow
• In data-mode the unit starts looking for the Escape-sequence if there is no data from DTE (Data Terminal
Equipment) for more than 20 ms (Start Guard Time).
• If the unit detects the Escape-Sequence:
• The transmitter continues sending over the air the data received from DTE before Escape- Sequence and
buffers the data from DTE;
• The Receiver immediately stops forwarding to DTE the data received over the air and buffers it instead.
• The radio unit waits for 20 ms and then sends Escape-Acknowledge to DTE if there is no data from DTE
during 20 ms of Stop Guard Time.
• The unit goes to command mode and discards Escape-Sequence from input buffer. The modem is imme-
diately ready to receive commands. At the same time it continues buffering the data received over the air
since step 2.
Escape-Sequence in Data
During its waiting in step 3, the unit receives data from DTE:
• The unit sends buffered Escape-Sequence from DTE to the air;
• The unit sends all buffered data received from the air since step 2 to DTE and stays in data-mode (i.e.
transmits data received from DTE over the air – including the just received, unexpected, data and forwards
data received over the air to DTE.)

Switching to Data Mode

• DTE sends the CLI command "DATAMODE<CR><LF>" to the unit.
• Unit answers with Escape-Acknowledge („@00<CR><LF>") and immediately goes to datamode, so that
the DTE can start sending data as soon as the Escape-Acknowledge has been received.
• If no valid CLI commands received from DTE within 1 minute, the unit will automatically switch back to
data-mode.
14
Table 1. Command Line Interface Error Codes
Command Syntax Error. A command followed by "/?" displays a command usage.
The parameter has a format error. A command with the certain [Parameter Name] followed by "/?"
displays the format and range of the variable.
The parameter is out of allowed range. A command with the certain [Parameter Name] followed by
"/?" displays the format and range of the variable.
The command is not valid for specific radio model. To display the list of available commands, the
HELP command must be used.
Unspecified Error
Short Description
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