Kantronics KPC-4 - Page 10

To change a command setting you type the command, a space, the argument (a
number or whatever is appropriate), and then the RETURN or ENTER key. If you turn
the TNC off and back on again the changes will not be remembered unless you have
used the PERM command, or are using a Battery Backup or SmartWatch.
All commands are listed alphabetically in the Commands Manual, and many are
discussed by mode in this Operations Manual. The Commands Manual also has an
introduction that goes into more detail on the structure of commands.
Asynchronous Commands
Asynchronous commands are commands that allow your TNC and computer to talk
the same language. These commands in the TNC will have their counterparts in your
computer program, although some programs may limit what you can set. Following is
a list of TNC defaults and their corresponding computer settings. Then we will explain
the commands using both the computer and the TNC terminology.
TNC Computer
ABAUD 0 The TNC runs an autobaud routine to allow it to match the speed
- set in your computer when the TNC receives an asterisk.
8BITCONV ON Data Bits or Word Length 8
PARITY 4 Parity no or none
ECHO ON Full Duplex
XFLOW ON Software Flow Control
Baud Rate is how fast the computer and TNC will talk to each other. This is set in the
TNC with the ABAUD command. The settings allowed by the TNC are 0, 300, 600,
1200, 1800, 2400, 4800, and 9600. (KPC-1 only allows 0, 300, 1200, and 9600.) When
set to 0, the autobaud routine will run at power-up — requiring you to press the
asterisk whenever you turn on the TNC.
Word Length and Data Bits are often used interchangeably to refer to how many
bits are used to recognize a character. Each character is made up of smaller parts
called bits (analogous to a dit or dah in morse code). These bits are seen as high or low
voltages on the cable between the TNC and computer to make the desired combination
for a character. A standard by the name of ASCII allows 8 bits for each character,
although all the standard alphanumeric characters and punctuation can be recognized
with only 7 bits. The TNC will talk to the computer using either 7 or 8 bits depending
on the setting of the command 8BITCONV. As defaulted SBITCONV ON means 8 bits.
Set 8BITCONV OFF to strip the 8th bit and use only 7 bits.
Parity determines what the 8th bit will be and is an old form of error detection which
few modern-day programs check. PARITY 4 is the default'in the TNC which means the
8th bit will be seen as part of the character. Odd or Even Parity will change the 8th bit
depending on whether there is an odd or even number of high voltages in the 7-bit
character. Mark and Space Parity will hold the 8th bit either high or low. In the TNC,
setting PARITY 0 is odd parity; PARITY 1 is even parity; PARITY 2 is mark parity;
PARITY 3 is space parity; and PARITY 4 is no parity. 8BITCONV must be ON before
the TNC will look at the 8th bit (the TNC always sends the 8th bit in Transparent
Mode).
Stop Bits. The TNC always uses 1 stop bit.
4 INTRO
: © Copyright 1989, 1990, Kantronics, Inc. All Rights Reserved.
Version 3.0 Aug. 13, 1990 Duplication of this manual or the firmware without
Operations Manual permission of Kantronics, Inc. is prohibited.