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Profile Setup via 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 sup-
plier). Either method allows quick and easy editing of
profiles.
Note: There is a global block on profile creation or
editing via Modbus while a profile is running. An at-
tempt to do so returns the error code 0x15.
The only profile related commands allowed while a
profile runs are the Profile Control & Status Param-
eters in the previous section.
Advanced users can setup or edit profiles by writing
to the Profile Configuration parameter at address 8198
(0x2006). This can only be accessed 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 pro-
file at the next available position, or at the position you
specify.
Each message in the sequence includes a 2 byte Com-
mand Code that tells the instrument the purpose of the
message, and therefore the meaning of the data con-
tained 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 posi-
tion and links it to the segment created in step 2.
4. Continue writing segments until the profile is com-
plete (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 seg-
ments can be added to the specified profile. To add
a segment to an existing profile the insert segment
command must be used.
Instruction Sequence to create a profile at a speci-
fied profile position:
If this profile number is already in use then the
profile header data is overwritten but the seg-
ments 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 posi-
tions 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 Mes-
sage.
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 posi-
tion and links it to the segment created in step 2.
5. Continue writing segments until the profile is com-
plete (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.
6. The very last segment of the profile must be one
of the end type segments. Thereafter, no more seg-
ments can be added to the specified profile. To add
a segment to an existing profile the insert segment
command must be used.
Instruction Sequence to edit an existing
Profile Header
When a profile header is changed, the segments asso-
ciated with it remain unchanged. They must be edited
separately if required.
1. Determine the number of the profile to be edited.
Use the Command Code value PS (0x50, 0x53)
which returns a list of all profile positions/numbers
currently in use.
2. Write a new profile header data using the Command
Code value EP (0x45, 0x50). The profile number is
echoed back by the instrument in the Edit Response
Message.
Summary of Contents for Chromalox 4081
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