Siemens SIMATIC S5 Manual page 109

S5-115F Manual
Transfer operation
During transfer, information from ACCUM 1 is copied into the addressed memory area, e.g. into
the PIQ.
This transfer does not affect the contents of ACCUM 1.
When transfer to the digital output area occurs, the byte or word in question in the PIQ is auto-
matically updated.
Example: Figure 3-3 shows how byte a (the low-order byte in ACCUM 1) is transferred to QB 5.
ACCUM 2
Byte d Byte c
Byte d Byte c
Transferring an input/output value with TPY/TPW operations:
The TPB/TPW transfer operations are output in both subunits. The PIQ is updated at the same
time.
In the case of single-channel I/O modules, these operations only affect the occupied subunit.
EWA 4NEB 811 6149-02
ACCUM 1
Byte b Byte a
T QB 5
Byte b Byte a
Figure 3-3. Transferring a Byte
STEP 5 Operations
Information Lost
in the PIQ information
Previous value
Byte a
of QB 5
3-13