Parker Compax3 Fluid T40

Parker EME
Communication
192-121102 N04 June 2008 361
Upload/download objects via the Profibus
All settings of Compax3 can be read using the Profibus and written back to
Compax3. This makes it easy to replace a device, for example.
Compax3 must be configured (once running through the configuration wizard
followed by a download is enough; the configuration settings are, however, not
relevant)
To implement this, the PKW mechanism has been changed.
Structure of modified PKW:
Byte 1 Byte 2 Byte 3 Byte 4 Byte 5 Byte 6 Byte 7 Byte 8
PKE IND PWE
PKW: Parameter identification value
PKE: Parameter identification (1. and 2. octet) (see below)
IND: Object index (3. octet high 4. octet low)
PWE: Parameter value (5. to 8. octet)
Structure of modified PKE:
Byte 1 Byte 2
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
AK=14 or 15 SPM DF DPZ SI
AK: Order/response identification
SPM: Reserved
DF: Data format (DF=1 constant)
DPZ: Data buffer access
SI: Object subindex
Data buffer access:
For each object, 16 bytes must be read or written. Since the size of the PWE
channel is 4 bytes, each object must be read or written 4 times.
Sequence for reading / writing and object:
DPZ=0:
Order executed
Object byte 1 ... 4 can be read / is being written
DPZ=1 Object byte 5 ... 8 can be read / is being written
DPZ=2 Object byte 9 ... 12 can be read / is being written
DPZ=3 Object byte 13 ... 16 can be read / is being written
The data will either be read fro the PWE or written into the PWE.
Access algorithm for reading objects
 Object 20.2 written with value 0 (object 20.2 is a counter that specifies the next
object to be read; the starting value is 0).
 Read object index and subindex in object 20.5.
Format I32 of Object 20.5:
Not assigned Index (high byte) Index (low byte) Subindex
 Read the object with the index and subindex read in object 20.5 and in save it in
a table with the following structure: Index (2Byte), Subindex(1Byte), Contents
(16Byte).
 Read the next object-Index and subindex in object 20.5.
 ....
This must be performed until index = 0xFFFF and until subindex = 0xFF.
Writing objects
Write the entire table to Compax3. Each index and subindex is written with the
value stored in the table.
Condition: