Introduction.

Workshop PG5
Program structures
5.3 Function Blocks ( FB 0 to 999 )
What’s a FB:
FB's ( Function blocks ) are nearly the same as PB's. Similar to PB's, FB's contain
program parts which can be called from other blocks. This call can be conditional or
unconditional.
The unique difference is that FB's give you the possibility to call the block with parameters,
as where with PB’s, you cannot.
FB's with parameters can only be called from an IL program.
The following example shows a FB which makes an output blink.
The FB is called twice. First it makes the output 64 blink at a rate of 1.5 seconds
and the second output 65 at a rate of 3 seconds.
Call a FB:
; Function block program
FB 1 ; Function Block 1
STL =2 ;If timer = L
LDL =2 ; then load the time
=3
COM =1
EFB
; and toggle the output
;The FB ends here
; End function block
; Main program
;-------------------
COB 0 ;Program start
0
;Call function block
CFB 1 ;Call the FB 1
O 64
T 1
15
;Call function block
CFB 1 ; Call the FB 1
O 65
T 2
30
ECOB
;End main program
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