B&K Precision 4079 - Manual - Manual (Page 50)

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SOURCE:FREQUENCY 3KHZ;:OUTPUT:STATE ON
Common Commands may be inserted in the Program Message without affecting the instrument-control command
reference. For example,
SOURCE:VOLTAGE:AMPLITUDE 4V;*ESE 255;OFFSET 2V
FOR MODEL 4079 ONLY:
Exclusively for the model 4079 with multiple channels, the selection of which channel to use is achieved through the use of a
numeric suffix indicating the channel, attached to the root level mnemonic. Four root level mnemonics are channel-
dependent, and these are SOURce, TRIGger, OUTPut and ARBitrary. When the channel is not specified, channel 1 is
assumed by default. Program message units that are referred back to a specific root level mnemonic operate on the channel
specified in that mnemonic.
Examples:
a) SOUR:FREQ 5KHZ;VOLT:AMPL 3V
Sets the frequency and amplitude of the first channel (default).
b) SOUR2:FREQ 5KHZ;VOLT:AMPL 3V
Sets the frequency and amplitude of channel 2.
c) ARB2:START 100;LENGTH 50
Sets the start address and length of the waveform being output on channel 2.
4.11 Status Reporting
The instrument is capable of reporting status events and errors to the controller, using the IEEE 488.1 Service Request
function and the IEEE 488.2 Status Reporting structure.
4.11.1 The Status Byte
Status summary information is communicated from the device to the controller using the Status Byte (STB). The STB is
composed of single-bit summary-messages, each summary message summarizing an overlying Status Data Structure. By
examining the content of the STB, the controller gains some information concerning the instrument's status.
The STB bits are defined as follows:
Bit 0: Unused
Bit 1: Unused
Bit 2: Error/event queue summary message (EVQ). This bit is set if the queue is not empty.
Bit 3: Questionable Status summary message.
Bit 4: Message Available (MAV) summary message. This bit is set whenever all or part of a message is available for the
controller to read. The controller may be ready to read the response message before it is available, in which case it can
either wait until this bit is set, or it can start to read. In the second case, the controller timeout must be set so that the read
action will not be aborted before the message has been read.
Bit 5: Event Status Bit (ESB) summary message. This bit is set to indicate that one or more of the enabled standard events have
occurred.
Bit 6: Request Service (RQS). This bit is set when the device is actively requesting service.
Bit 7: Operation Status summary message. No Operation Status events are defined in the instrument, and so this bit is never
set.
The STB is read by the controller during a serial poll. If the RQS bit was set, it is then cleared. The STB may also be
read by the *STB? common query.