NF WAVE FACTORY WF1967, Инструкция по эксплуатации

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11.2 Basics
WF1967/WF1968 11-10
j) Limitation of available waveform
The waveforms that can be used for sequence oscillation are limited to sine wave, square wave
(both standard and extended duty variable range), noise, DC, and arbitrary waveform.
When you wish to use a ramp wave or parameter-variable waveform, copy the desired waveform to
the arbitrary waveform and save it as an arbitrary waveform in advance in the ARB Edit screen.
During sequence oscillation, it is not possible to specify the symmetry of ramp wave or the
parameters of the parameter-variable waveform.
When you wish to use a pulse waveform, save the half sine edge pulse of the parameter-variable
waveform as an arbitrary waveform.
k) Waveform size
The waveforms used in the sequence are not written to the waveform memory each time the step is
executed. Before the execution of sequence, the waveforms are expanded to the 1MiW waveform
memory (per channel) during compilation. Therefore, when many types of waveforms are used, a
memory size allocated to each waveform becomes consequently smaller. However, since DC and
square wave (regardless of whether the duty variable range is standard or extended), they do not use
the waveform memory. In addition, the required memory size does not change when the same
waveform is used repeatedly. The number of types of waveform that can be used is limited to 128.
Beware of the following points:
•
When the allocated memory size becomes small, an arbitrary waveform in the control point
format with many abrupt changes may lose the characteristics of the waveforms.
•
When a large-waveform is used in an arbitrary waveform in the array format, the memory size
allocated to other waveforms becomes smaller.
The following table shows the memory size that can be allocated to each waveform.
Waveform Size Size adjustment
DC 0W Fixed
Square wave 0W Fixed
Sine wave 4KiW, ...512KiW, 1MiW (power of 2) Variable
Noise 32KiW Fixed
Arbitrary waveform (control
point format)
4KiW, ...512KiW, 1MiW (power of 2) Variable
Arbitrary waveform (array
format)
4KiW, ...512KiW, 1MiW (power of 2) Fixed
When a parameter-variable waveform, square waveform, pulse waveform, or ramp waveform is
copied to an arbitrary waveform, it becomes an arbitrary waveform in control point format.
Noise is always used in a memory size of 32KiW. The size is fixed. However, this does not mean
that the same pattern is repeated during output.
An arbitrary waveform in the array format is used with the waveform size, which is transferred from
USB or GPIB, and the size is fixed.
A sine wave and an arbitrary waveform in the control point format are allocated to the remaining
memory size, which is 1MW minus the total size of the fixed-length waveform shown above. The
waveform size is adjusted based on the free memory space and the number of waveforms. However,
all memory sizes allocated to each variable-length waveform are the same.
The arbitrary waveforms in the control point format are not simply thinned but expanded to the
memory in a way, so that the characteristics of the waveform are maintained as much as possible.
Caution: In the initial setting, waveforms in all steps are sine wave and the step terminal is set to
[Continue]. If the initial setting is not changed, when a 1MiW arbitrary waveform in the array
format is specified in an arbitrary step, an error occurs during compilation due to insufficient
memory space to allocate the sine wave to the waveform memory. When using a 1MiW arbitrary
waveform in the array format, create a sequence which does not go through the steps requiring
another waveform memory.