Festo EXCM-10-***-E, Перевод оригинальной инструкции, Страница: 51 / 84

6 Operation
Festo – EXCM-10/-30-...-E-EN – 1612b – English 51
6.5.3 CVE protocol
Access to the data of the controller is through CVE objects. A CVE object always has a unique index that
enables identification of the object.
Note
A series of CVE objects is listed in the appendix (
è
C.1 CVE object overview).
Caution
Personal injury and material damage
Inadvertent writing to non-documented objects can result in unforeseeable behaviour of
the planar surface gantry.
Use only objects listed in the appendix (
è
C.1 CVE object overview).
Each CVE object has one of the following listed data types (
è
Tab. 6.12 Data types).
The byte sequence is Little Endian, that is, the lowest-value byte first.
Data types
Value Type Bytes Description Range of values
0x00 – – Unknown data type –
0x01 – – – –
0x02 UINT32 4 32 bit unsigned integer 0 … 4294967295
0x03 UINT16 2 16 bit unsigned integer 0 … 65535
0x04 UINT08 1 8 bit unsigned integer 0 … 255
0x05 – – – –
0x06 SINT32 4 32 bit signed integer – 2147483647 … 2147483647
0x07 SINT16 2 16 bit signed integer – 32767 … +32767
0x08 SINT08 1 8 bit signed integer – 127 … +127
Tab. 6.12 Data types
Read object
To read a CVE object, a request corresponding to Tab. 6.13 must be sent to the controller. This sends
back a response corresponding to Tab. 6.14.
Write object:
To write a CVE object, a request corresponding to Tab. 6.15 must be sent to the controller. This sends
back a response corresponding to Tab. 6.16.
As both directions concern an endless TCP data stream, the individual messages must be filtered out
from this. Specification and strict compliance with the message length are required for this.