Fluke 5500A - Compound Commands; Coupled Commands

5500A
Operator Manual
5-28
Table 5-5. IEEE-488 Interface Messages (Send)
Mnemonic Name Function
END End A message that occurs when the 5500A asserts the EOI control
line. The 5500A asserts EOI while it transmits the ASCII character
LF for its termination sequence or terminator.
DAC Data Accepted Set the handshake signal line NDAC low.
DAV Data Valid Asserts the handshake signal line DAV.
RFD Ready for Data Sets the handshake line NRFD low.
SRQ Service
Request
A control line that any device on the bus can assert to indicate that
it requires attention. Refer to “Checking 5500A Status” for details.
STB Status Byte The status byte is what the 5500A sends when it responds to a
serial poll (interface message SPE).
5-29. Compound Commands
A compound command is two or more commands in a single command line. For
example, the following two commands could be entered individually,
OUT 1 V, 60 Hz
OPER
where the 5500A Calibrator sources 1 V ac at 60 Hz, and then goes into operate, or they
could be combined into a compound command,
OUT 1 V, 60 HZ ; OPER
using a semi-colon as a separator. Care must be taken when a compound command
includes any of the coupled commands. (See “Coupled Commands.”)
5-30. Coupled Commands
A coupled command refers to two or more commands that appear in a compound
command (see “Compound Commands”) that perform actions that could interfere with
each other causing a fault. Commands in a compound command are separated by using
the ; character. Compound commands using only coupled commands are not order-
dependent.
In Chapter 6, the command graphic shows a check mark for
Coupled
x
commands.
The five coupled commands are:
CUR_POST HARMONIC WAVE
DC_OFFSET OUT
An example of coupled command interference is the command
OUT 1 V ; RANGELCK ON
followed by the command
OUT 10 V ; RANGELCK OFF
which can’t be executed because RANGELCK ON in the first command locks the dc volts
range, preventing the command OUT 10 V from executing. With a different order
RANGELCK OFF ; OUT 10 V
the second compound command can executed successfully.