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Teledyne LeCroy X-STREAM OSCILLOSCOPES Remote Control User Manual

Page 23

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Control by GPIB

WM-RCM-E Rev D

ISSUED: February 2005

17

DEVICE CLEAR

In response to a universal Device CLear (DCL) or a Selected Device Clear message (SDC), the X-Stream DSO

clears the input or output buffers, cancels the interpretation of the current command (if any) and clears
pending commands. However, status registers and status-enable registers are not cleared. Although DCL will

have an immediate effect, it can take several seconds to execute if the oscilloscope is busy.

GROUP EXECUTE TRIGGER

The Group Execute Trigger message (GET) causes the X-Stream DSO to arm the trigger system, and is
functionally identical to the *TRG command.

REMOTE ENABLE

X-Stream DSOs do not lock out any local controls when placed in the remote state, or in RWLS. It always
accepts remote as well as local control inputs (unless you turn off remote control capability in UtilitiesÆ
Remote.)

INTERFACE CLEAR

The InterFace Clear message (IFC) initializes the GPIB but has no effect on the operation of the
X-Stream DSO.

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: To illustrate the GPIB programming concepts, a number of examples are included here,

written in a similar way to BASIC. It is assumed that the controller is IBM-PC compatible, and that it

is equipped with a National Instruments GPIB interface card. Nevertheless, GPIB programming with

other languages such as C or Pascal is quite similar. If you’re using another type of computer or

GPIB interface, refer to the interface manual for installation procedures and subroutine calls.
This procedure refers to the installation and configuration of a GPIB card under the DOS operating

system. More recent operating systems (Windows 95, 98, ME, NT, 2000, XP, etc) generally use ‘Plug

‘n’ Play’ GPIB drivers, which are configured using an icon in the control panel.

CONFIGURE THE GPIB DRIVER SOFTWARE

Verify that the GPIB interface is properly installed in the computer. If it is not, follow the interface

manufacturer’s installation instructions. In the case of the National Instruments interface, it is possible to
modify the base I/O address of the board, the DMA channel number, and the interrupt line setting using

switches and jumpers. In the program examples below, default positions are assumed.

Connect the X-Stream DSO to the computer with a GPIB interface cable.

Set the GPIB address to the required value. The program examples assume a setting of 4.