SP Scientific ULTRA-COOL, Руководство оператора

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RS-232 Programmer’s Reference Ultra-Cool
34 Rev 008, 01/12
© SP Scientific 2012
Received Data
Data may be transmitted at any time by the host. Status queries will be answered
whether or not the unit is in local or remote. Any change in system status (except
"Goto Remote") requested via the RS-232, however, will require that the unit be in the
"remote" state; otherwise an error will be reported to the host.
Data uses a "line" format, consisting of the following:
CMD <opt CMD> <opt CMD> <...> CR <opt LF>
CMD is any valid transmitted data string.

CR is an ASCII "Carriage Return."

LF is an ASCII "Line Feed."

Data commands may be grouped within a "line" command, or transmitted singly. A
data string must be terminated by a "Carriage Return" (ASCII 013 decimal / 0D
hex)."Line Feed" (ASCII 010 decimal / 0A hex) may be optionally inserted by the host,
but will be ignored. A "line" may not exceed 128 characters.
A listing and description of the available CMD statements appears in a later section.
Data commands that are grouped on a line must be separated by a single "Space"
(ASCII 032 decimal / 20 hex).
The Delete/Rubout character (ASCII 127 decimal / 7F hex) will NOT be recognized.
Unrecognized characters will result in an error acknowledge.
ANY error in transmission/reception of a "line" will assume corruption of the
ENTIRE line, and ALL commands in that line will be ignored. This includes not
only transmission (
e.g.
, parity) errors, but values out of bounds, undefined
commands,
etc
. This ensures that state changes are not presented to the
system (
e.g
., new Setpoint SP) without all corresponding desired changes
(such as corresponding PID values).
All data received by the target system will be presented by the host system as a
character string of one of the following formats:
Absolute Command 1.
Basic system functions/commands will consist of a fixed character string.
Examples
START
Wake up system

STOP
Shut down system

POLL
Force a response from the system
