Specifications

40 MDS 4790/9790 Series I/O Guide MDS 05-3438A01, Rev. E
Continuous
Transmitter Keying
CKEY [ON/OFF]
The
CKEY command enables or disables continuous keying. When CKEY
is enabled (
ON), the radio is continuously keyed. The CKEY command is
normally enabled when the radio is in a full-duplex master configura-
tion.
Data Interface
clear-to-Send Period
CTS [0-255]
This command displays or sets the timer value associated with the CTS
line response. Entering the
CTS (Clear-to-Send) command without a
parameter displays the timer value in milliseconds. Entering the
CTS
command with a parameter ranging from 0 to 255 sets the timer value in
milliseconds. The timer value function depends on the radio’s operating
mode (DCE or CTS Key). See the
DEVICE command for more informa-
tion about these operating modes.
When the radio is in DCE mode, the timer specifies how long to wait
after the RTS line goes high before asserting the CTS line. A timer value
of zero means that the CTS line will go high immediately following
RTS.
When the radio is in CTS Key mode, the timer specifies how long to
wait after asserting the CTS before sending data out the
DATA INTER-
FACE port. A timer value of zero means that data will be sent out the data
port without imposing a keying delay. (Other delays may be present,
depending on how other operating parameters are configured.)
Should you experience problems with repeater operation after changing
the
CTS, PTT or SCD values, contact MDS.
Transmitter Keyed
on Incoming Data
DATAKEY [ON/OFF]
This command displays or sets the keying mode. In key-on-data mode,
the radio will automatically key itself whenever input data arrives on the
DB25 port. In key-on-RTS mode, the radio will only key in response to
an RTS or PTT signal (or the
KEY command).
Entering the
DATAKEY command alone shows whether the keying mode
is key-on-data (
ON) or key-on-RTS (OFF). Entering the DATAKEY com-
mand followed by a parameter controls whether or not the radio will
automatically key on receipt of data. The
ON parameter sets the radio to
key-on-data mode. The
OFF parameter sets the radio to key-on-RTS
mode. The default mode is key-on-data.
Continuous Keying screen,
Page 68
A
B
Clear-to-Send Delay screen,
Page 66
A
B
Key On Data screen, Page 69
A
B