Chapter 2 - Connecting your Computer
10
Transmit data:
This line is the serially transmitted data from the terminal to the KAM.
Receive data:
This line is the serially transmitted data from the KAM to the terminal.
Request to send:
This line tells the KAM that the terminal is ready to receive data. An ON level
tells the KAM it may send data while an OFF level tells it to stop sending
data.
Clear to send:
This line tells the terminal whether or not it may send data to the KAM. An
ON level tells the terminal it may send data while an OFF level tells it to stop
sending data.
Data Carrier Detect: This line is an output from the KAM indicating connected status of the unit.
When a connection exists on the current stream, this line will be true. (When
using TTL levels, DCD at +5 V indicates connected status.)
Signal ground:
This line establishes the common ground reference potential for all circuits
except Protective Ground.
Data set ready/
Data terminal ready: These pins are common on the KAM connector and are held high.
Mark/Space:
These signals are available for connecting an external scope if desired. Refer
to the section covering this implementation for instruction.
+12 V:
This is an alternate input pin for supplying power to the KAM if desired. If
the normal 12 VDC input jack is used, this pin will be hot. BE CERTAIN THIS
PIN IS NOT CONNECTED TO YOUR COMPUTER!
INTRODUCTION TO COMMANDS
There are some very specific procedures which must be observed when talking to the KAM.
The internal program in the KAM has an extensive set of program routines which allows it to do
what you want done and report the results back to you. This short section will give you a familiar-
ity with the procedures needed to initially manipulate the unit. For a further explanation and dis-
cussion see Chapter 6 - Commands and Messages.
COMMAND STRUCTURE
You communicate with the KAM by using commands entered at your computer. Some com-
mands are actually "instructions" to the KAM. These tell it to perform a certain action or report in-
formation to you. For example, the
Connect
command tells KAM to make a connection to the sta-
tion you specify or tell you its current state if no connection exists. Another example, the
RTTY
command tells KAM to go to the RTTY mode of operation.
Other commands set "parameters" or additional values which control actions that KAM will take
or conditions which will exist during its operation. For example, the
MYcall
command requires that
you add a value to it, i.e. your station callsign, which will be used in all Packet communications. A
parameter, or additional value, may be a number or it may be a "flag" having only two possible
settings – ON or OFF. Examples of these are
MAXUsers
, which may have a number from 0 to 26,
and
Monitor
, which may be ON or OFF.
You will see many of the commands in KAM which set two indicated parameters or "sides".
These commands are displayed with a slant bar ( / ) separating the two presently set values.
These commands have a separate parameter or value for each of the radio ports. The value dis-
played to the LEFT of the bar is for use with the HF port and the value displayed to the right of the
bar is for use with the VHF port. You may set the required values independently or at the same
time according to the following rules: