Introduction.

Workshop PG5
Resources
3.2 Internal (software) resources
3.2.1 Flags
How to use
Flags in your
program:
1 bit (0/1) of information
F NV ( non volatile )
0 8191
A flag memorizes one bit of information. There is 8192 flags. (0 is a valid
flag). By default, the flags are non volatile. This means that if you turn off the
PCD, and the flag is a 1, when you turn the PCD back on, it will still be a 1.
(Considering that your battery is good). All volatile flags would be reset to a 0,
if the PCD was turned off). If you want a volatile flag or flags, they can be
configured in the software settings. This is explained below.
The following example writes a high (1) into the Flag number 11 as soon as
inputs 1 or 3 is high. Boolean equation: F 11 = I 1 + I 3
Instruction list program:
COB 0
0
STH I 1
ORH I 3
OUT F 11
ECOB
FUPLA program:
(FBox: Binary, OR 2 to10 inputs)
Setup flags:
By default the flags aren’t volatile. If you want them to be volatile, then you
have to specify so in the software settings. (See example)
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