Receiving Data S7-400
n If a receiving CPU with a BRCV block ready to accept data (that is, a call with EN_R
= 1 has already been made) goes into STOP mode before the corresponding send
block has sent the first data segment for the job, the following will occur:
n The data in the first job after the receiving CPU has gone into STOP mode are fully
entered in the receive area.
n The partner SFB BSEND receives a positive acknowledgment.
n Any additional BSEND jobs can no longer be accepted by a receiving CPU in STOP
mode.
n As long as the CPU remains in STOP mode, both NDR and LEN have the value 0.
n To prevent information about the received data from being lost, you must perform a
hot restart of the receiving CPU and call SFB 13 BRCV with EN_R = 1.
14.2.9 FB/SFB 14 - GET - Remote CPU read
The FB/SFB 14 GET can be used to read data from a remote CPU. The respective CPU
must be in RUN mode or in STOP mode.
Please note that this block calls the FC or SFC 200 AG_GET internally.
These must not be overwritten! The direct call of an internal block leads
to errors in the corresponding instance DB!
Depending upon communication function the following behavior is present:
n Siemens S7-300 Communication (FB 14)
– The data is read on a rising edge at REQ. The parameters ID, ADDR_1 and
RD_1 are transferred on each rising edge at REQ. After a job has been com-
pleted, you can assign new values to the ID, ADDR_1 and RD_1 parameters.
n Siemens S7-400 Communication (SFB 14)
– The SFB is started with a rising edge at REQ. In the process the relevant pointers
to the areas to be read out (ADDR_i) are sent to the partner CPU.
Parameters
Parameter Declaration Data type Memory block Description
REQ INPUT BOOL I, Q, M, D, L control parameter request, a rising edge activates
the data exchange (with respect to the most
recent FB/SFB-call)
ID INPUT WORD I, Q, M, D,
constant
A reference for the connection. Format:
W#16#xxxx
NDR OUTPUT BOOL I, Q, M, D, L Status parameter NDR: data from partner CPU
has been accepted.
ERROR OUTPUT BOOL I, Q, M, D, L Status parameter ERROR:
n ERROR = 0 + STATUS = 0000h
– No warnings or errors.
n ERROR = 0 + STATUS unequal to 0000h
– A Warning has occurred. STATUS con-
tains detailed information.
n ERROR = 1
– An error has occurred.
Description
VIPA SPEED7
Integrated Standard
System Function Blocks > FB/SFB 14 - GET - Remote CPU read
HB00 | OPL_SP7 | Operation list | en | 18-30 742
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