Stanford Research Systems DS345, Manual

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Arbitrary Waveform Editing
2-32
VECTOR EDITING
Described below are the methods for editing vector format arbitrary wave-
forms. Each stored data value (vertex) contains an x value (address in wave-
form RAM) and y value (amplitude). The vertices in the data list are connect-
ed by straight lines when the DS345 loads the waveform RAM. For a given
vertex, the display is switched between x and y values by pressing [STEP
SIZE].
Vertex Number
The vertex number can be set to any value between 0 and the number of ver-
tices in the current waveform. The absolute maximum vertex number is 6143
(there can only be 6144 vertices in a waveform). The vertex number may be
set using either the keypad or the MODIFY up/down keys. If the vertex num-
ber is set past the end of the waveform (where there is no data) an "edit er-
ror" will result.
x Value
The vertex x value is the location of the vertex in waveform RAM. This value
may range from 0 to 16299. Each vertex must have a x value equal to or
greater than that of the previous vertex, and if two or more vertices have the
same x value only the first is loaded (the rest are ignored). If the first vertex
of the waveform does not have an x value of 0 (the start of memory) the
DS345 will automatically add a vertex at 0,0. If the x value has no data (be-
fore a value has been entered, for example) the data will be displayed as five
dashes (-----).
y Value
Each vertex may have an amplitude value ranging between -2048 and +2047
(12 bit DAC). If a vertex has no value (before a value has been entered) the
data will be displayed as five dashes (-----).
Adding a vertex at the
end of the waveform
To add a vertex at the end of the waveform set the vertex number to the last
1 (vertex 4, for example, if 0,1,2,3 are filled). The value will be dis-
played as ----- (indicating no data yet). Enter a new value for either x or y. If x
is entered first y will be set to 0, while if y is entered first x will be set to the
value of the previous vertex (0 for the first vertex).
Deleting a Vertex
To delete a vertex, enter the vertex number of the vertex to be removed.
Then, with the vertex number active (flashing) press [CLR]. The remaining
vertices will be renumbered if necessary.
Duplicating a Vertex
To duplicate a vertex, enter the vertex number of the vertex to be copied.
Then, with the vertex number active (flashing) press any UNITS key. The ver-
tex will be duplicated (both x and y) and the vertex number incremented to
display the new vertex.
Inserting a Vertex
To insert a vertex in the middle of a waveform, duplicate the vertex currently
at the insertion point. Then, modify the new vertex to the desired value.