AMCI NR60E2, Руководство пользователя

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5.4 Implicit Messaging Data Format (continued)
5.4.2 Assembly Instance = 3
As shown in the table below, when you set the Input Assembly Instance to 3, the input data consists of the
position value and velocity data transferred as two 32 bit double integers.
Table T5.3 Input Data, Position and Velocity
5.5 Buffer Implicit Messaging Data
Implicit Messaging data is updated asynchronously to the scan at the programmed RPI time. Therefore, this
data should be buffered by copying it to holding registers using a Synchronous Copy (CPS) instruction. The
holding registers are then used by your PLC program. If the data is not buffered, it can change during a pro-
gram scan, resulting in logical errors that may cause a machine malfunction.
Figure T5.5 Sample CPS Instruction
The amount of data to buffer depends on the Input Assembly Instance you chose while adding the NR60E2 to
your host controller. When transferring position data only (Assembly Instance =1), the length should be “1”.
When transferring position and velocity data, (Assembly Instance = 3), the length should be “2”.
DINT # Description
0
Position Data.
The maximum position value depends on your NR60E2 model and the
programmed counts per turn. The maximum value in all cases is 1,073,741,823
(16#3FFF FFFF).
1
Velocity Data.
The units of measure of the velocity data is set by the Velocity Format
parameter in the Configuration Data. If the Scaling Function Control bit is ever
set to a “1”, the position data used to calculate the velocity data is always scaled
by the Measuring Units per Span parameter.
Synchronous Copy File
Source
Dest
Length
AMCI_NR60_DLR:I.Data[0]
NR60_DLR_InBuffer
[1 or 2]
CPS