Version 3.6
20
1)
The inter-character delay will be increased by at least the time of the modem transfer delay
2)
The probability of collisions on the radio path will increase. This will be especially harmful for
repeater chains
The default value for the Pause length is 3 bytes.
6.2.1
Data buffering in the radio data modem
A synchronisation signal is transmitted at the beginning of each radio transmission and this
signal is detected by another radio modem, which then turns into receive mode. During the
transmission of the synchronisation signal the radio modem buffers the data to be transmitted
into its memory. Transmission ends when a pause is detected in the data flow sent by the
terminal device, and after all the buffered data has been transmitted. When the data speed of
the serial port is the same or slower than the speed of the radio interface, the internal transmit
buffer memory can not overflow. However, when the serial interface speed exceeds the speed of
the radio interface, data will eventually fill the transmit buffer memory. After the terminal device
has stopped data transmission, it will take a moment for the radio modem to get the buffered
data transmitted and get the transmitter switched off. The maximum size of transmit buffer
memory is one kilobyte (1 kb). If the terminal device does not follow the status of the CTS line
and transmits too much data to the radio modem, the buffer will be cleared and the
transmission is restarted.
In the receiving mode, the data coming from the radio is also buffered thus evening out
differences in data transfer speeds at the serial ports.
6.2.2
TX delay
The radio modem can be configured to delay the beginning of a radio transmission by
1...65000 ms. During this delay data sent to the radio modem is buffered.
