Maple Systems OIT Family (ASCII) User Manual
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Except for the command initiator (ESC control character) and the command or line
terminator, all other characters sent by the host must be ASCII printable characters.
There are two types of terminators used in control commands: the command terminator and
the line terminator. The command terminator is the STX control character and is used to in-
dicate the end of a control command. The line terminator is programmable and can be CR,
LF, CR/LF, or ETX. The line terminator is used by the ASCII host to indicate the end of a
control command or to “log off” an OIT when operating in Network mode (refer to the “Op-
erating Modes” section).
The OIT immediately responds to the ASCII host’s control commands with an error code,
any requested data, and a line terminator.
Notation Conventions
this section uses the following type styles to define control command syntax:
SMALL CAPS
Used for ASCII control characters that are non-printable.
Control characters are sent to the OIT using decimal or hexadecimal
notation or by sending a BASIC CHR$ command. The control
characters can also be generated from the keyboard of a computer
when
using a terminal emulation program. The table, below, lists the
control characters recognized by the OIT when sent by the ASCII host:
bold
Used for literal portions of the syntax that must be used exactly as
shown (including upper/lower case).
italics
Used for variables that specify the type of data to include.
Note: Spaces are shown between the segments of the control command for clarity only.
Spaces should not actually be sent. For example,
ESC
A text terminator should be sent as
ESC
Atextterminator.
Control
Character
Decimal
Notation
Hexadecimal
Notation
BASIC
Command
Terminal Keyboard
Keypresses
ESC
27
1B
CHR$(27)
CTRL [
STX
2
02
CHR$(2)
CTRL B
CR
13
0D
CHR$(13)
CTRL M
LF
10
0A
CHR$(10)
CTRL J
ETX
3
03
CHR$(3)
CTRL C
Control Command Format
initiator commandletter commanddata terminator
initiator =
ESC
command letter = printable ASCII character A, M, O, P, Q, R, S, or W
command data = any data required by the specified command
terminator = command terminator
STX
or line terminator
CR
,
LF
,
CR/LF
, or
ETX
Command Response Format
errorcode commanddata lineterminator
error code = 0-6 (refer to the Error Codes table)
command data = any data required by the specified command
line terminator =
CR
,
LF
,
CR/LF
, or
ETX
OPERATION
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1010-0088, REV02