RKC PF900 SpecView support for Patterns and Segments.

The SpecView support for the RKC PF900 is split into two SpecView ‘Instruments’:

The Controller part of the PF900 (Instrument called ‘RKC PF900 Controller’) and:
One for Pattern 1, Segments 1-64 (called ‘RKC PF900 Pattern 1’).

The Pattern 1 instrument allows the user to easily create and modify pattern 1 in the controller from a SpecView recipe screen – all the components of the segments are on screen at one time, and all can be read simultaneously.


Suppose the instrument is at Modbus Slave address 5.  Create a ‘PF900 Controller’ at address 5,0  to access the controller parts and also, if needed, create a ‘PF900 pattern 1’ at exactly the same address.

Using the ‘PF900 Pattern 1’ Instrument:

In addition to all the segment data, there are also the following extra parameters at the beginning of the list:


Operation Mode

RESET stops a program running, PROG starts running the pattern number specified in ‘Execute Pattern Number’

Hold State

Status of hold.

Step Function

Allows the programmer to step to the next segment

Execute Pattern Number

Set this before changing Operation Mode to PROG to run this pattern number

Running Pattern No

Shows which pattern is running

Running Segment No

Shows which segment is running

Pattern End State

Status of Pattern End

Segment Remaining time

Segment remaining time in whole minutes (H:M mode0 or whole seconds (M:S mode)

Pattern Remaining time

Pattern remaining time in whole minutes (H:M mode0 or whole seconds (M:S mode)

Pattern Number Select

Sets the pattern number for the next few parameters

Segment Number Select

Should not be used in this instrument, will have no effect

Pat: Program End no

Specifies the end segment number in the Pattern selected.

Pat: Seg Repeat Times

Setup up a segment repeat loop with the following start and stop

Pat: Seg Repeat Start


Pat: Seg Repeat End


Pat: Pattern Repeats

Sets the number of times to repeat th pattern

Pat: Link Pattern No

Links patterns together


Programming Other Patterns or other segments not included above.

This is done using what we call ‘keyhole surgery’.  In the controller instrument, at the end, there are the components of a single segment, as well as Pattern and Segment number selection parameters. There are also the various Pattern controls as well as the segment controls.

To program a pattern, proceed as follows:

Set the ‘Pattern Number Select’ to the desired pattern number.
Fill in any data in the ‘Pat:’ parameters that are to do with the Pattern.
Set the ‘Segment Number Select’ to each segment in turn. When this parameter is set, then the ‘Seg:’ parameters allow the reading and writing of that segment’s data. Once the segment has been programmed, move to the next segment number by changing ‘Segment Number Select’ and setting the data etc

Using this mechanism, it is possible to program up to 99 segments in a pattern, or up to 99 patterns of a smaller number of segments.

To setup a recipe screen using this keyhole surgery, please call SpecView for help.  It is possible, but requires more work.


SCADA software for people with other jobs!

(C) 2024  SpecView Inc & SpecView Ltd.  Page Updated: 09 January 2024