Siemens SIMATIC S5 Manual page 319

IP 266
START
yes
Was TOGGLE
bit="1"?
no
Bit 7 is set to "1" in
FY 6 (preset in
FB 21 to 24).
FY 6 is loaded into
QB 65.
END
FB 25 is invoked only if a command edge flag was set (in FB 21 to FB 24).
FB 20 - Read actual values
The IP 266 provides three modes for reading out IP data (see Section 5).
The default mode is mode 71, which is used to read the actual position.
Since mode 71 is to be used in the example, it need not be explicitly started. In
contrast to the other modes, modes 71 to 73 can also be started while the axis is
traversing ("Running" status).
The first part of the program in FB 20 displays the errors flagged in IB 67.
EWA 4NEB 812 6057-02
FB 25 - NAME:TOGGLE
Programming the TOGGLE bit: Inverting the
bit from the preceding job
Scanning the TOGGLE bit from the preceding
job
TOGGLE bit was "0"; invert TOGGLE bit in
command flag byte FY 6
Bit 7 is set to "0" in
FY 6 (preset in
FB 21 to 24).
FY 6 is loaded into
QB 65.
TOGGLE bit was "1"; invert TOGGLE bit in
command flag byte FY 6
INVT
STEP 5 Programming
A Q 65.7
JC =INVT
L FY 6
L KH 0080 TOGGLE BIT "1"
OW
T QB 65
BEU
L FY 6
L KH 007F TOGGLE BIT "0"
AW
T QB 65
BE
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