Fluke Calibration 5560A - USBTMC Interface Overview; How to Use Commands

5560A/5550A/5540A
Remote Programmers Manual
18
USBTMC Interface Overview
The USBTMC interface uses the bulk-out endpoint to send GPIB ATN=FALSE program messages to
the Calibrator. The bulk-out endpoint is also used to send trigger command messages to the Calibrator.
The bulk-in endpoint receives GPIB ATN=FALSE response messages from the Calibrator.
The Calibrator uses the interrupt-in endpoint to request service (it sends an SRQ message to the
controller) and to communicate the status byte register value. The SRQ condition communicated
automatically whenever the RQS bit is set in the Status Byte Register.
The control endpoint is used to send initiate clear (DCL,SDC) messages, REN enable messages
(REN), GO_TO_LOCAL (GTL), LOCAL_LOCKOUT (LLO) and READ_STATUS_BYTE (SPL).
How to Use Commands
Communications between the controller and the Calibrator consists of commands, queries, and
interface messages. Although the commands are based on the 488.2 standard, they can be used on
either the IEEE-488, USBTMC, Ethernet or RS-232 interface, except for a few specialized RS-232/
Ethernet commands described in Commands for RS-232/Ethernet Only. (For more information on
command structures, see the IEEE 488.2 standard.)
Refer to Remote Commands when you require additional information about command references used
this section.
All commands and units may be entered in UPPER or lower case.
There are four specific remote control configurations that use commands, queries and interface
messages: IEEE-488/GPIB, USBTMC, RS-232/Ethernet Terminal Mode, and RS-232/Ethernet
Computer Mode.
IEEE-488/GPIB Mode Use the IEEE-488/GPIB mode when the Calibrator is operated by computer
program. In this mode, requested information is returned by query, and interface messages are queued
and returned by command.
USBTMC Mode Use the USBTMC mode when the Calibrator is operated by computer program. In this
mode, requested information is returned by query, and interface messages are queued and returned
by command.
RS-232/Ethernet Terminal Mode The RS-232 and/or Ethernet terminal mode is an interactive mode
where an operator inputs commands, with immediate returns for requested information (queries) and
interface messages.
RS-232/Ethernet Computer Mode Use the RS-232 and/or Ethernet computer mode when the Calibrator
is operated by computer program. In this mode, requested information is returned by query, and
interface messages are queued and returned by command.