Chapter 7 - Commands and Messages
55
DWait
n
default 8/8
n
may be set to any value between 0 and 255, each increment specifying 10 ms intervals. This
value is used to avoid collisions with digipeated packets. The unit will wait
n
× 10 ms after last
hearing data on the channel before it begins its own keyup sequence. This value should be estab-
lished and agreed on by all members of a local area network. The best value will be determined by
experimentation but will be a function of the keyup time (
TXdelay
) of the digipeater stations. This
feature is made available to help alleviate the drastic reduction of throughput which occurs on a
channel when digipeated packets suffer collisions. Digipeated packets are not retried by the digi-
peater but must be restarted by the originating station. If all stations specify
DWait
, and the right
value is chosen, the digipeater will capture the frequency every time it has data to send since di-
gipeated packets are sent without this delay.
Echo
ON|OFF
default ON
When ON, characters received from the terminal by the unit are echoed back and displayed. If
you are receiving double print of letters entered at the keyboard, turn this command OFF.
EScape
ON|OFF
default OFF
This command specifies the character which will be output when an escape character is to be
sent to the terminal. When ON, the escape character ($1B) is sent as $24. When OFF, $1B is used.
This command is useful if your terminal interprets ESC characters as screen positioning commands.
EXcardet
ON|OFF
default OFF/OFF
When ON, the KAM will be dependent on the input of an external carrier detect signal on the
radio connector. This carrier detect signal must be provided by the radio for the KAM demodulator
circuits to be enabled. This input may be used in the same manner as a "squelch" input to allow
the KAM to detect activity on a shared-mode channel.
EXTmodem
ON|OFF
default OFF
When ON, the optional external modem is used on the VHF radio port.
Fec
xxxx
This command sets the unit in FEC mode. When a selcall is specified,
xxxx
, the unit will call a
specific station
xxxx
using
SELFEC
. Also see
AUTOStrt
command.
FIlter
ON|OFF
default OFF
This command can be used to inhibit the printing of control characters which may be encoun-
tered in Monitored packets. This will be useful if you are monitoring channel traffic which includes
transparent binary file transfers. Control characters which may be embedded in those packets can
have strange and unpredictable effects on the monitoring KAM. This command also inhibits the
printing of control characters in ASCII Mode.
FLow
ON|OFF
default OFF
When
FLow
is ON, any character entered from the terminal will halt output to the terminal until
the current line of input is completed.
FLow
will keep received data from interfering with data en-
try.
FRack
n
default 4/4
n
may be set to any value between 1 and 15, each increment specifying 1 second intervals.
After transmitting a packet requiring acknowledgment, the KAM waits
FRack
seconds before incre-
menting the retry counter and sending the packet again. If the retry count specified by
RETry
com-
mand is exceeded, the current operation is aborted. If the packet address includes relay requests,
the time between retries is adjusted to
FRack
× (2 ×
m
+ 1) where
m
is the number of intermedi-
ate relay stations specified. When the retried packet is sent, a random wait time is also added to
avoid lockups where two units repeatedly collide with each other.