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APPENDIX 2 - PROGRAM LOOPING AND NESTED 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 Time | Temp Hum | LS Rep Digital Channels |
dd:hh:mm:ss °C
00000:00:00:00
001 | 00:00:00:01 | 25.0 | 65 |
002 | 00:00:00:20 | 85.0 |
|
003 | 00:00:00:40 | 35.0 |
|
004 | 00:00:01:00 | 65.0 |
|
005 | 00:00:01:20 | 15.0 | 2 (2 reps + original) |
006 | 00:00:01:40 | 25.0 | 65 |
(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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