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Table 3-8. ieee 488 (gpib) bus data mode messages, 2 dcl control, 3 changing the gpib address – KEPCO BHK-MG 200W (Full Rack) Series User Manual

Page 61: 4 external trigger, Dcl control -17, Changing the gpib address -17, External trigger -17, Ieee 488 (gpib) bus data mode messages -17, 4 and b.92.)

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BHK-MG (OPR) 022014

3-17

3.3.2

DCL CONTROL

The device clear (DCL) and selected device clear can be set to operate in two modes. In the
“output = 0” mode, when the device clear is received the output is disabled; when the output is
enabled, the output of the power supply is set to zero volts and current is set to the power-up
and reset current value (see PAR. 3.2.8.1). In the “output unchanged” mode sending DCL or
selected DCL disables the output, but has no effect on output voltage and current as required by
IEEE specification 488.2 so that when the output is enabled, the settings in effect when DCL
was issued are restored. Note that the DCL setting also affects the operation of RESET (see
PAR. 3.2.8). The factory default value is “output=0” mode.

To change the DCL mode the unit must be in command entry mode

(:_:_:)

, then depress the

MENU key until the top line of the display shows the current setting: either

DCL OUTP = 0

or

DCL = OUTP UNCHNG

. Depress 1 for “output unchanged” mode where the output is unaffected

by DCL; depress 0 for “output = 0V” mode where DCL sets the output to 0 volts and current is
set to the power-up and reset current value (see PAR. 3.2.8.1).

3.3.3

CHANGING THE GPIB ADDRESS

When the power supply is in command entry status

(:_:_:)

, press MENU key until the top line

of the LCD indicates the current GPIB address. Enter new value and press ENTER to accept
new setting, or CLEAR to exit without changing setting. The GPIB address default value is set
to 6.

3.3.4

EXTERNAL TRIGGER

The External Trigger Port can be used to restore the power supply output to settings previously
defined using SCPI commands. This can be done by applying a temporary short between pin 4
and pin 1 of the External Trigger Port, (or if pin 4 is at TTL logic 1, applying a temporary logic 0
to pin 4 referenced to pin 1).

NOTE: Turn off power to the unit or disable the output before inserting the plug in the External

Trigger port to avoid unintentionally initiating shutdown or trigger.

The following remote SCPI commands must be sent before the external trigger at pin 4 acti-
vated:

• The values to be set upon receiving the external trigger at pin 4 must be programmed

using VOLT:TRIG (PAR B.58) and CURR:TRIG (PAR B.48) commands.

TABLE 3-8. IEEE 488 (GPIB) BUS DATA MODE MESSAGES

MNEMONIC

MESSAGE DESCRIPTION

COMMENTS

DAB

Data Byte

Received or Sent

END

End

Received or Sent

EOS

End of String

Received or Sent

RQS

Request Service

Sent

STB

Status Byte

Sent