Parker ACR Series, Руководство программиста

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Parker Hannifin
The "arc direction" bit in header code 1 indicates the direction of
the arc relative to the primary and secondary axes. A counter-
clockwise arc is defined as an arc from the positive primary axis
toward the positive secondary axis.
The radius of the arc will be equal to the distance between the arc
target position and the given center point. If the arc target position
is equal to the target position of the previous move, a 360-degree
path will be generated. The target position of the previous move
must lie on the defined arc or the axes will jump to that location
before the arc begins.
If the "incremental center" bit in header code 3 is set, the center
points are relative to the current target positions of the slaves,
otherwise the center points are absolute. The "floating point data"
bit in header code 3 indicates that the given center points are in
IEEE floating point format, otherwise they are long integers.
NURB or SPLINE Moves
When the "NURB or Spline" bit in header code 3 (Bit 6) is set, the
move data packet includes NURB or Spline curve data. In addition,
bit 5 and 6 in header code 1 will differentiate if the data is NURB or
Spline. Bit 5 of header code 1 is set when Spline data includes Knots.
The control points for NURB and Spline are sent as DATA3 thru
DATA10, similar to the way the normal slave targets are sent. Load
the Knot in DATA13 and Weight in DATA14 and set the Bit 3 of code
3.
Binary SET and CLR
The immediate setting and clearing of bits can be accomplished
with a 3-byte binary command sequence. This sequence is a 1-byte
command header followed by a two-byte index value. The index
value is sent low order byte first. The command is not queued and
the set or clear occurs when the command is first seen by the board.
Binary SET
Data Type Description
Byte 0 Header ID ( 0x1C )
Byte 1 Index Byte 0
Byte 2 Index Byte 1
Byte 3 0x00, this byte is for
ACR8020 DPCB only.
120 Programmer’s Guide