Operator Manual Firmware Ver.3.05 and higher Instruction Manual

BOP-1K-GL 022814 3-35
power supply operation (such as setting voltage/current). Common commands and queries are
preceded by an asterisk (*) and are defined and explained in Appendix A (see Table 4-4). Refer
also to syntax considerations (PARs 3.4.3 through 3.4.6).
3.7.3 SCPI SUBSYSTEM COMMAND/QUERY STRUCTURE
Subsystem commands/queries are related to specific power supply functions (such as setting
output voltage, current limit, etc.) Figure 3-9 is a tree diagram illustrating the structure of SCPI
subsystem commands used in the BOP Power Supply with the “root” at the left side, and spe-
cific commands forming the branches. The following paragraphs introduce the subsystems;
subsystem commands are defined and explained in Appendix B.
3.7.3.1 ABORT SUBSYSTEM
This subsystem allows pending trigger levels to be cancelled.
3.7.3.2 INITIATE SUBSYSTEM
This subsystem enables the trigger system. When a trigger is enabled, the triggering action will
occur upon receipt of a GPIB <GET>, *TRG or TRIGger command. If a trigger circuit is not
enabled, all trigger commands are ignored.
3.7.3.3 LIST SUBSYSTEM
The LIST subsystem is used to generate transients, waveforms and execute a series of steps
(points) repeatedly. Up to 1002 power supply settings can be stored temporarily. Each setting
consists of either a voltage or current value (depending on whether the power supply has been
set to Voltage or Current mode), and a corresponding dwell time (the duration those settings are
in effect). These settings may be executed in sequence as they are entered, or executed in a
user-determined sequence that also allows individual settings to be repeated more than once.
In addition, the entire sequence may be repeated for a specific number of times, or run indefi-
nitely until commanded to stop. The sequence can also be run in reverse order to produce
inverted waveforms.
Each point contains a value for the main channel (either voltage or current) and the duration
(dwell) that the value will appear at the output (from 93 microseconds to 0.034 second. The list
system supports from 2950 to 5900 points per waveform, depending on the number of different
dwells in the waveform: For example, if each point in the list has the same duration (a single
dwell time), 5900 points are supported; if no more than 126 different dwell times are specified,
3933 points are supported, and if each point has a different dwell, a maximum of 2950 points
are supported. The number of points supported is determined automatically by the BOP firm-
ware.
The LIST subsystem includes a subsystem for waveform generation. The waveform generation
is invoked with the verb APPLY. When APPLY is added to a list:volt or list:curr command, the
BOP adds a series of points to the list arrays. The BOP can apply these points to approximate a
SINE, Triangle, RAMP (positive or negative) or square waveform or a level. The basic command
requires a type, frequency (or period for a level), a peak-to-peak amplitude (or amplitude for a
level).and offset (offset not needed for a level) The unit will create an appropriate number of
points in both the dwell and output control array to create the waveform centered on zero volts.
An optional offset can be added to the command to cause the BOP to generate a non-centered
waveform. For example, a 5 volt 400 Hertz sine wave may be centered at -3 volts. The list sub-
system allows the user to modify the unit's behavior to generate parts of waveforms and to used
specific dwell times as appropriate. The APPLY subsystem accommodates 126 different seg-