Parker ACR Series, Руководство программиста

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Parker Hannifin
Binary Data Packets
Packets allow binary access to system parameters at any time. This
method must be used if commands are sitting in the input queue
since
PRINT statements would also be buffered. The packet is the
quickest way to access information such as current position and
following error for display in an application program.
Packet Request
Packets are requested by sending a four-byte binary request record.
The following is a list of the bytes contained in this record:
Data Field Description
Byte 0 Header ID ( 0x00 )
Byte 1 Group Code
Byte 2 Group Index
Byte 3 Isolation Mask
Group Code and Index
The group code and group index work as a pair to select the data
coming back in a data packet. The group code selects a general
data grouping and the group index selects a set of eight fields
within that group. The isolation mask then selects which of these
eight fields is to compose the final data packet.
Isolation Mask
The isolation mask acts as a filter to select only the specific data
required (for example, actual position for AXIS 2, AXIS 3 and AXIS 5.)
If a bit is set in this mask, the corresponding data field is allowed to
return in the data packet. In order to return all eight fields, the
isolation mask must be 0xFF. Mask Bit0 is used to isolate the first field
in a group and Bit7 is used to isolate the last field.
Binary Host Interface 101