Honeywell HC900 User Manual
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HC900 Hybrid Controller Communications User Guide
Revision 10
12/07
Procedure for Downloading Setpoint Profile
These steps are for programmer 1. For programmers 2, 3, 4, 5, 6, 7, and 8 adjust the register addresses
accordingly by adding offset for starting addresses.
Table 6-7 is for downloading using Function Codes 3, 4, 6, 16.
If using a custom map, you need to know the addresses of the parameters referred to in this procedure. Use
HC Designer to print a report showing the Modbus registers of the SP Programmers.
Table 6-7 Steps to Download a Setpoint Program using Modbus Function Codes 3, 6, 16
Step Action
1
Set the programmer to RESET by writing any number to Reset parameter (p. 60). This can
be done either with function code 6 or 16.
2
Clear the program by writing a 0 to Current Program Number (p. 60). This is a floating point
register and requires a multiple register write (function code 16). This is the safest way to
insure that all registers are cleared for the next program download.
3
Write the header information for parameters relevant to the profile (leave all others at 0).
See Table 6-9 items marked with **. Do not write yet to Program Save Request (p. 60).
Floating point registers must be written using function code 16. Bit-packed registers can be
written with either function code 6 or 16.
Note: Display High Range Limit and Display Low Range Limit (p. 60) are not presently used
in the HC900 but can be used on external operator interfaces.
4
Write the information for each segment required in the profile. Each segment uses 8
registers and all 400 registers of the 50 segments are contiguous. See Table 6-10. The first
2 registers of each segment are bit-packed and can be written with either function code 6 or
10; the last 6 registers are float and must be written using function code 16.
5
Save the program to a program (profile) number archive by writing a floating point number
to Program Save Request (p. 60). This will store the downloaded data utilized by the
programmer block to the program (profile) number used. Profile numbers may range from
1-99.
The program is now ready to run. Note that the Current Program Number (p. 60) is automatically set
to the saved program number.
Procedure for Uploading Setpoint Programs
If using a custom map, you need to know the addresses of the parameters referred to in this procedure. Use
HC Designer to create a report showing the Modbus registers of the SP Programmers.
Table 6-8 Steps to Upload a Setpoint Program using Modbus Function Codes 3, 6, 16
Step Action
1
Set the programmer to RESET by writing any number to the address (p. 60). This can be
done either with function code 6 or 16.
2
Load the program into the setpoint programmer block by writing the program number to
Current Program Number (p. 60). This is a floating point register and requires a multiple
register write (function code 16).
3
Using function code 3, read the header information desired. See Table 6-9 items marked
with **.
4
Read the information for each segment desired using function code 3. See Table 6-10.