Despatch Protocol 3 Modbus Communications - Manual (Page 36)

A DDRESS LIST Modbus Programming Manual
36 Version 2
Copyright © 2012 by Despatch Industries.
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Command Code Value Decimal Value Hex Function
RS 21075 0x5253 Read Segment
PN 20558 0x504E Read Profile Name
PS 20563 0x5053 Read the profiler memory status
The following rules apply when creating a profile over communications:

Profiles must always be terminated with an end segment.

Segments cannot be added after an end segment has been added.

All changes made to the selected profile are immediately saved in the instrument.
2.9.1. 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.
2.9.2. Instruction Sequence to create a profile at a specified profile
position
CAUTION:
If this profile number is already in use then the profile header data is overwritten but the segments
associated with it are kept.
1. Determine which profile positions are being used by using the Command Code value PS
(0x50, 0x53). This command will return a list of all the profile positions currently being
used.
2. Choose a location that is not being used and write the profile header data using the
Command Code value WP (0x57, 0x50).
The profile number is echoed back by the instrument in the Edit Response Message.
3. 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.
4. 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.