L3 Systems KeyAT, Manual

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KeyAT Keyboard Port Adapter
L3 Systems 7 5/19/2007
Sending Data
The main job of a KeyAT is to transfer data from the RS-232 or
RS-485 port and send it through to the computer's keyboard
port. Data can be sent using ASCII, ASCII control codes, DOS
scan codes, keyboard scan codes or ASCII hex. If you are
using line turn around mode or if the KeyAT is addressed, a
line can have a maximum length of 46 characters and should
end with an <ENTER> (CR, hex 0D). When using immediate
mode, data and commands are interpreted as received, and
buffered up to 46 characters. If you get more than 46
characters ahead of the computer, the additional characters
will be ignored. Characters are not echoed when the KeyAT is
addressed.
If the KeyAT is addressed, a colon is sent back immediately to
acknowledge that the data was received. If the KeyAT is not
addressed and in line turn mode, a colon is sent back after
the data has been processed, signaling that another command
can be sent. The following example shows the ASCII
characters ‘DIR<ENTER>’ being sent through the KeyAT.
Example:
KeyAT 2.0x, [C]L3 Systems, 1996-2003
:DIR^M<ENTER>
:
Commands
Commands are instructions to the KeyAT to do something
other than just pass data through to the computer. All
commands begin with a ~ (tilde, hex 7E) character followed by
a command character and then in some cases some data.
~@ Disable Commands
– All commands are disabled until 10
consecutive tildes (~~~~~~~~~~) or reset/power cycle.
~~~~~~~~~~ Reset/Enable Commands
– If commands are
disabled, this will enable commands. If