Siemens SIMATIC S5-115U User Manual page 398

Integral Blocks
The FETCH Block - FB246 -
FB246 requests that data can be fetched from a communications partner over a CP. The data is re-
ceived via function block FB245 in RECEIVE ALL mode. You can use the FETCH block only to fetch
data for a specific job (FETCH DIRECT function).
Calling the FETCH Block (Example)
STL
: JU
NAME : FETCH
SSNR :
A-NR :
ANZW :
ZTYP :
DBNR :
ZANF :
ZLAE :
PAFE :
:
***
Description of the FETCH Function
All parameters must be assigned for the FETCH function. The destination parameters (ANZW,
ZTYP, DBNR, ZANF, ZLAE) are passed to the CP during handshaking. As soon as the requested data
arrives, the CP provides the RECEIVE ALL block with both parameters and data. The FETCH block
itself does not transfer or receive data.
The FETCH job is activated under the following conditions:
• RLO "1" has been forwarded to the function block.
• The CP has enabled the function. (The "SEND/FETCH in progress" bit is "0").
If "RW" is assigned to the ZTYP parameter, the FETCH block transfers the source and destination
parameters and the address of the job status word to the CP.
FETCH can be invoked in the cyclic program or in an interrupt service routine. The FETCH or CON-
TROL block updates the job status word.
11-24
FB 246
KY 0,10
KY 0,101
FW 9
KS DB
KY 0,46
KF + 5
KF + 20
FY 14
S5-115U Manual
CSF/LAD
FB246
FETCH
SSNR PAFE
A-NR
ANZW
ZTYP
DBNR
ZANF
ZLAE
EWA 4NEB 811 6130-02b