Fluke 5520A Operator's Manual page 182

5520A
Operators Manual
Mnemonic
ATN
DAC
DAV
DCL
END
GET
GTL
LLO
IFC
MLA
MTA
REN
RFD
SDC
SPD
SPE
UNL
UNT
5-28
Table 5-4. IEEE-488 Interface Messages (Received)
Name
Attention A control line that, when asserted, notifies all instruments on the bus
that the next data bytes are an interface message. When ATN is
low, the next data bytes are interpreted as device-dependent or
common commands addressed to a specific instrument.
Data Accepted Sets the handshake signal line NDAC low.
Data Valid Asserts the handshake signal line DAV.
Device Clear Clears the input/output buffers
End A message that occurs when the Controller asserts the EOI signal
line before sending a byte.
Group Execute Trigger a TC measurement and put the reading in the output buffer.
Trigger
Go To Local Transfer control of the 5520A from one of the remote states to one
of the local states. (See Table 5-1)
Local Lockout Transfers remote/local control of the 5520A. (See Table 5-1)
Interface Clear A control line that sets the interface to a quiescent state.
My Listen Addresses a specific device on the bus as a listener. The controller
Address sends MLA automatically whenever it directs a device-dependent or
common command to a specific instrument.
My Talk Addresses a specific device on the bus as a talker. The controller
Address sends MTA automatically whenever it directs a device-dependent or
common query to a specific instrument.
Remote Enable Transfer remote/local control of the 5520A. (See Table 5-1.)
Ready For Sets the handshake signal line NRFD low.
Data
Selected Does the same thing as DCL, but only if the 5520A is currently
Device Clear addressed as a listener.
Serial Poll Cancels the effect of a Serial Poll Enable.
Disable
Serial Poll After the 5520A receives this message, it sends the Status Byte the
Enable next it is addressed as a listener, no matter what the command is.
Unlisten "Unaddresses" a specific device on the bus as a listener. The
controller sends UNL automatically after the device has successfully
received a device-dependent or common command.
Untalk "Unaddresses" a specific device on the bus as a listener. The
controller sends UNL automatically after the device has successfully
received a device-dependent or common query.
Function