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8 program message syntax summary, 9 status reporting, 1 status reporting structure – KEPCO MBT Series User Manual

Page 101: Program message syntax summary -63, Status reporting -63, Status reporting structure -63

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MBTSVC111609

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3.3.5.8

PROGRAM MESSAGE SYNTAX SUMMARY

• Common commands begin with an asterisk (*).

• Queries end with a question mark (?).

• Program messages consist of a root keyword and, in some cases, one or more message

units separated by a colon (:) followed by a message terminator. Several message units
of a program message may be separated by a semicolon (;) without repeating the root
keyword.

• If a program message has more than one message unit, then a colon (:) must precede

the next keyword in order to set the parser back to the root (otherwise the next keyword
will be taken as a subunit of the previous message unit).

e.g., the command meas:volt?;curr? will read output voltage and output current

since both volt? and curr? are interpreted as subunits of the meas command.

• Several commands may be sent as one message; a line feed terminates the message.

Commands sent together are separated by a semicolon (;). The first command in a mes-
sage starts at the root, therefor a colon (:) at the beginning is not mandatory.

e.g., the command meas:volt?;:curr? will read output voltage and programmed cur-

rent since the colon preceding curr? indicates that curr? is not part of the meas com-

mand and starts at the root.

• UPPER case letters in mnemonics are mandatory (short form). Lower case letters may

either be omitted, or must be specified completely (long form)
e.g., INSTrument (long form) has the same effect as INST (short form).

• Commands/queries may be given in upper/lower case (long form)

e.g., SoUrCe is allowed.

• Text shown between brackets [] is optional.

e.g., :[SOUR]VOLT:[LEV] TRIG has the same effect as :VOLT TRIG

3.3.5.9

STATUS REPORTING

The status reporting of the MBT-G power supply follows the SCPI and IEEE 488.2 require-
ments. The serial poll response of the MBT-G power supply provides summary bits of the status
and error reporting system. The simplest status report is the command valid reporting and data
availablity, This successful decoding of a command string generates no error and is indicated by
the bit 3 of the serial poll response being a zero. The setting of bit 4 in the status byte indicates
data is available to the controller in response a command query message.

3.3.5.9.1 STATUS REPORTING STRUCTURE

The status reporting of the MBT-G power supply uses four status registers, illustrated in Figure
3-6. These registers are the Questionable, Operation, Standard Event and Service Request reg-
isters. The Questionable and Operation registers are 16 bit registers and the Standard Event
and Service Request registers are 8 bits. These four registers are referred to as condition regis-
ters. Each of the four condition registers is associated with two related registers: an event regis-
ter which holds unlatched events reported in realtime by the instrument and is cleared by