3-6
IM 701310-17E
3.6 Responses to Interface Messages
Responses to Interface Messages
Responses to a Uni-Line Message
•
IFC (Interface Clear)
Clears the talker and listener functions. Stops output if data are being output.
•
REN (Remote Enable)
Switches between the remote and local modes.
IDY (Identify) is not supported.
Responses to a Multi-Line Message (Address Command)
•
GTL (Go To Local)
Switches to the local mode.
•
SDC (Selected Device Clear)
• Clears the program message (command) being received and the output queue (see
page 6-5).
• *OPC and *OPC? commands in execution are void.
• The *WAI and COMMunicate:WAIT commands are immediately terminated.
PPC (Parallel Poll Configure), GET(Group Execute Trigger), and TCT (Take Control)
are not supported.
Responses to a Multi-Line Message (Universal Command)
•
LLO (Local Lockout)
Disables
CLEAR
on the front panel to prohibit switching to the local mode.
•
DCL (Device Clear)
Same operation as the SDC message.
•
SPE (Serial Poll Enable)
Sets the talker function on all devices on the bus to serial polling mode. The controller
polls the devices in order.
•
SPD (Serial Poll Disable)
Clears the serial polling mode of the talker function on all devices on the bus.
PPU (Parallel Poll Unconfigure) is not supported.
What Are Interface Messages
Interface messages are also referred to as interface commands or bus commands. They
are commands that are issued by the controller. They are classified as follows:
Uni-Line Messages
A single control line is used to transmit uni-line messages. The following three types are
available.
• IFC (Interface Clear)
• REN (Remote Enable)
• IDY (Identify)
