Profile setup over modbus – West Control Solutions ProVU 4 User Manual

Page 114

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ProVU4 Controller, Profiler & Recorder/Controller - Product Manual

59407, Issue 1 – March 2008

Modbus Parameters

Page 113

Profile Setup Over Modbus

The information in this section is intended for advanced users writing their own software
code. Most users will create or edit profiles using the instrument keypad, or using the the PC
software (available from your supplier). Either method allows quick and easy editing of
profiles.

Advanced users can setup or edit profiles by writing to the Profile Configuration parameter at
address 8198 (0x2006), This can only be access by using Modbus function code 23 (0x17).
The instrument replies with a status message.

When creating a new profile the steps below must be followed exactly, either to create a
profile at the next available position, or at a position that you specify.

Each message in the sequence includes a 2 byte Command Code that tells the instrument
the purpose of the message, and therefore the meaning of the data contained in it.

Instruction Sequence to create a profile at the next available position

1. Create a profile by writing the profile header data using the Command Code value CP

(0x43, 0x50). This starts the profile creation process by reserving a profile memory slot.
The profile number is returned by the instrument in the Edit Response Message.

2. Write the first segment using the Command Code value Code WS (0x57, 0x53). This

command will fill the next available segment position and link it to the profile created in
step 1.

3. Write the second segment, again using Command Code WS. This fills the next available

segment position and links it to the segment created in step 2.

4. Continue writing segments until the profile is complete (whilst remaining within the overall

limit of 255 segments for all profiles combined). Each of these segments fills the next
available position and links it to the previous segment specified.

5. The very last segment of the profile must be one of the end type segments. Thereafter, no

more segments can be added to the specified profile. To add a segment to an existing
profile the insert segment command must be used.

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