Quantum Composers 9500 Plus Series - Manual (Page 42)

38
Line Termination
The pulse generator uses text-style line terminations. When a command is sent
to the unit, the firmware is programmed to read characters from a
communication port until it reads the line termination sequence. The command
string is parsed and executed after reading these characters. These
characters are the “carriage return” and “linefeed”. They are ASCII character
set values 13 and 10 respectively (hex 0x0D and 0x0A). All command strings
need to have these characters appended.
When the pulse generator responds to a command, whether it is a query or a
parameter change, it also appends its return strings with these characters.
Coded applications could use this behavior to know when to stop reading from
the unit. However, if the “echo” parameter is enabled, there will be two sets of
line terminators, one following the echoed command string, and one following
the pulse generator’s response.
Note: The pulse generator will echo commands on the DB9 serial port only.
The pulse generator responds to every communication string. If the
communication string is a query, the unit responds with the queried response (or
error code) followed by the line terminators. If the communication string is a
parameter change, the response is “ok” (or error code) followed by the line
terminators. For this reason, it is not recommended that multiple commands be
stacked together into single strings as is common with some other types of
instruments. It is recommended that the coded application send a single
command in a string
and follow immediately by reading the response from the unit. Repeat this
sequence for multiple commands.
IEEE 488.2 Common Command Format
The IEEE 488.2 Common Commands control and manage generic system
functions such as reset, configuration storage and identification. Common
commands always begin with the asterisk (*) character and may include
parameters. The parameters are separated from the command pneumonic by a
space character. For Example:
*RST <cr> <lf>
*RCL 1 <cr> <lf>
*IDN? <cr> <lf>
SCPI Command Keywords
The commands are shown as a mixture of upper and lower case letters. The
upper case letters indicate the abbreviated spelling for the command. You may
send either the abbreviated version or the entire keyword. Upper and/or lower
case characters are acceptable.