Nova Electronics MCX514, User Manual

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NOVA electronics Inc. MCX514 -
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3.2.1 The Finish Point Checking of Circular Interpolation
In the circular interpolation, it assumes that the current position (start
point) is (0,0). The radius is determined depending on the value of the
center point coordinates, and then the circular tracking will start. The
maximum error range of interpolation is with in ±1LSB. Because of the
±1LSB error range, the designated finish point may not on the circular
track. When the current point is same or over the finish point of short
axis, this circular interpolation is finished in the quadrant where the
finish point is. If the current point cannot reach the finish point of short
axis, this circular interpolation is finished in the end of the quadrant
where the current point reaches.
Fig. 3.2-5 shows an example of CCW interpolation with the start point
(0,0), center point (−200,500) and finish point (−702, 299). The finish
point is in quadrant 4, and ax2 is the short axis in quadrant 4. So the
interpolation is finished when the ax2 is 299.
3.2.2 Toggle of Interpolation Axis
The interpolation axes are defined that the higher priority axis is set to ax1 (horizontal axis) and the lower priority axis is set to
ax2 (vertical axis) in order of priority X>Y>Z>U. However, the user can toggle between the two axes. When the user wants to
change the lower priority axis to ax1 (horizontal axis) and the higher priority axis to ax2 (vertical axis), set D4 bit of WR6 register
to 1 by interpolation mode setting command (2Ah).
3.2.3 The Example for CW Circular Interpolation
This CW circular interpolation starts from the current point (start point: 0, 0) to the finish point ( X: 5000, Y: −5000); the center
point is X: 5000, Y: 0. The interpolating speed is constant at 1000PPS in 2-axis simple constant vector speed driving.
WR6 ← 0043h Write ； define: ax1:X axis, ax2:Y axis, and with 2-axis simple constant linear speed
WR0 ← 002Ah Write
WR6 ← 03E8h Write ； 1000 PPS
WR7 ← 0000h Write
WR0 ← 0104h Write ； Set initial speed to main axis
WR6
← 03E8h Write ； 1000 PPS
WR7 ← 0000h Write
WR0 ← 0105h Write ； Set drive speed to main axis
WR6
← 1388h Write ； center point of X ： 5000
WR7 ← 0000h Write
WR0 ← 0108h Write
WR6 ← 0000h Write ； center point of Y ： 0
WR7 ← 0000h Write
WR0 ← 0208h Write
WR6
← 1388h Write ； finish point of X ： 5000
WR7 ← 0000h Write
WR0 ← 0106h Write
WR6
← EC78h Write ； finish point of Y ： -5000
WR7 ← FFFFh Write
WR0 ← 0206h Write
WR0 ← 0064h Write ； CW circular interpolation driving
Fig. 3.2-5 CW/CCW Circular Interpolation
Start point (0,0)
Center point
(- 200,500)
Finish point
(- 702,299)
ax2
ax1
Interpolation will be finished
when ax2=299 in the 4th
quadrant
.
0
1
2
3
4
6
7
Start point
(0,0)
Center point
(5000
,
0)
Finish point (5000,- 5000)
X
Y