Nova Electronics MCX514, Руководство пользователя

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3.1 Linear Interpolation
Any 2 or 3 axes or all the 4 axes can be set
for linear interpolation.
To execute linear interpolation, set the finish
point coordinates relative to the present point
coordinates, and write the linear interpolation
driving command based on the number of
interpolation axis, then linear interpolation
will be performed.
The finish point coordinates should be set in
output pulse number of each axis by the
relative value to the present point
coordinates.
Fig. 3.1-1 shows an example of 2-axis interpolation
where linear interpolation is performed from the
current coordinates to the finish point coordinates. As shown in the figure,
the calculation accuracy of position to the ideal line is within ±0.5 LSB.
As shown in Fig.
3.1-2
, it is an example
for pulse output of the linear
interpolation driving. We define the
longest distance movement in
interpolation is the “long axis”.
And the other is “short axis”. The long axis
outputs an average pulse train. The driving
pulse of the short axis depends on the long
axis and the relationship of the two axes.
When constant vector speed mode is disabled, the speed of the drive pulse in long axis becomes the drive speed for
the main axis.
The range for each axis is a 31-bit signed counter, from -1,073,741,823
～
+1,073,741,823 (signed 31-bit-2LSB).
3.1.1 Maximum Finish Point
The absolute value of the finish point in long axis is called the maximum finish point.
At the reset initial state of IC, the maximum finish point is automatically calculated, but the user can set it manually by
interpolation mode setting command (2Ah). If in manual setting, the user can specify the arbitrary value as the maximum finish
point. For more details of interpolation mode setting command (2Ah), see chapter 7.3.8.
3.1.2 Examples of Linear Interpolation
■
Example of linear interpolation for 2 axes
Executes linear interpolation in X and Y axes from the current position to the finish position ( X: +300, Y: −200). The
interpolation drive speed is constant: 1000PPS.
WR6
← 0003h Write ； map interpolation axis X, Y
WR0 ← 002Ah Write
WR6 ← 03E8h Write ； initial speed ： 1000 PPS
WR7 ← 0000h Write
WR0 ← 0104h Write
WR6
← 03E8h Write ； drive speed ： 1000 PPS
WR7 ← 0000h Write
WR0 ← 0105h Write
WR6 ← 012Ch Write ； finish point of X axis ： 300
100 200 300
-100
-200
Ｘ
Ｙ
(300,-200)
0
Fig. 3.1-1 Position Accuracy for Linear Interpolation
Fig. 3.1-2 Example of Pulse Output at Finish Point (X=20, Y=9)
5
10 15 20
5
(20,9)
0
Y
±0.5 LSB max
X
Long axis
Short axis
XPP
XPM
YPP
YPM
Long axis
Short axis