TS4000 Radio Modem User’s Manual
Radio Setup
28
During normal operation, the frequency channel can be switched on the fly with:
Channel Switching
1) A control String through either serial port.
2) The DTR and RTS control lines on serial port 2. For details, see Radio
Setup – Frequency Channel at Power Up.
3) Automatically with the Clear Channel Scan function. For details, see
Radio Setup – Frequency Channel at Power Up.
The channel is switched by sending the following ASCII character string to either
of the TS4000’s serial port.
Channel Change with
a Control String
+TSCxx
Where:
xx
= Channel number from 01 to 99
Note: The letter characters must be upper case.
The channel change control string is sent to the modem the same as standard
transmit data. For the control string to be recognized it must be the first
characters of a burst of transmit data. If the control string is sent alone (no data
following), then the TS4000 will switch to the receive frequency of the new
channel pair and wait in receive mode. If the control string is sent with a transmit
data burst following it, then the TS4000 will switch to the transmit frequency of
the new channel pair and transmit the burst.
The active channel can be determined with the channel query string. This is done
with the following ASCII character string.
Determining the Active
Channel
+TSC?
Note: The letter characters must be upper case.
The response string is sent out the serial port and is as follows.
1)
+TSCxx
For single channel systems
Where:
xx
= Channel number from 01 to 99
2)
+TSCCS
For modems configured for clear channel scan
If a frequency channel is selected that has not been programmed with valid
frequencies, the modem will not receive or transmit and the RX and TX lights will
alternately flash.
Invalid Channel Selection
The channel that the TS4000 activates at power up depends on the setting of the
Frequency Channel at Power Up control (see Radio Setup – Frequency Channel
at Power Up).
Channel at Power Up
