APPENDIX 2 - PROGRAM LOOPING ANDNESTED LOOPS
You can program loops in format550. In addition you can program loops within loops
(nesting). This section tells you how, with simple examples.

LOOP INSTRUCTIONS

The loop instructions are achieved using the "LS" & "Rep" columns that appear on the
program preparation sheet & on the program window of the system.
In the line from which you want to loop back:
in column "LS" you specify which line you want the program to loop
back to.
in column "Rep" you specify how many times you want the program to re-
peat this part of the program.
The program loops back from the time line in which the loop is listed, to the first line
in the loop.
EXAMPLE 1
Taking a simple example: You require the temperature to cycle from 25°C to 85°C, then
to 35°C, then to 65°C, then to 15°C, before returning to 25°C. But you want to cycle
through the 35/65/15 part three times in all before emerging at the final 25°C.
To do this you would program:
Seg
000
001
002
003
004
005
006
Time
dd:hh:mm:ss
00:00:00:00
00:00:00:01
00:00:00:20
00:00:00:40
00:00:01:00
00:00:01:20
00:00:01:40
Temp

°C

25.0
85.0
35.0
65.0
15.0
25.0
Hum
65
65
LS Rep Digital Channels
2 (2 reps + original)
(the times are unrealistic for environmental test purposes, but they provide a program
that can be cycled quickly to see the effects.)
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