Nova Electronics MCX514, User Manual

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NOVA electronics Inc. MCX514 -
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－ 125 －
3.4.1 Designation of Interpolation Axis
Interpolation axis can be specified by interpolation mode setting command (2Ah). As shown below, set D0~D3 bits of WR6
register, set 1 to the bit corresponding to the axis that interpolation is performed. Bit pattern interpolation can be performed with
from 2 axes to all 4 axes, but it cannot specify only 1 axis.
The other bits (D15
～
D4) of WR6 register are the setting bit related to interpolation. Please refer to 7.3.8, and set appropriate
values.
3.4.2 Interpolation Speed Setting
It sets the drive speed for bit pattern interpolation to the main axis among interpolation axes.
The drive speed can be set up to 4MHz at a maximum in bit pattern interpolation mode. However, if the bit pattern data is more
than 128 bits, the maximum speed will depend on the BP data update rate of a host CPU because the CPU is required to replenish
BP data to pre-buffer (described below) during interpolation driving.
For example of 2 axes bit pattern interpolation, the host CPU must write (16 bit data × 2 + 16 bit command) × 2 axes +
interpolation driving command in order to update BP data. If it take
s 100μsec, output time of 16 bit (=16 drive pulses) must be
longer than that. Thereby, interpolation drive speed must be lower than 1 /
(100μSEC / 16) = 160KPPS. If the higher value is set,
replenishment of BP data does not catch up.
3.4.3 Bit Pattern Data Writing
It writes bit pattern data for each interpolation axis.
Write bit data of 16 bit in the + direction to WR6 register, and write bit data of 16 bit in the - direction to WR7 register. The 16 bit
data will be output as drive pulse from D0 bit to the upper bit in turn.
When drive pulse number / finish point setting command (06h) is written with axis assignment in WR0 register, BP data is stored
in pre-buffer, which is applied to all interpolation axes.
Fig. 3.4-3 Bit Pattern Data Writing
WR6
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
H L
X
-EN
Y
-EN
Z
-EN
U
-EN
WR6
WR7
nPP( ＋ direction pulse)
1 1 1 1 1 1 1 1 1 1 1 0 0 1 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
D15
D0
D15
D0
WR0
nPM( － irection pulse)
06h
D8
D11
Axis assignment
BP data setting command