Hi Fedein,

The Gateway us transperent for the I/O thats behind it.

So for the outputs I think that the next programming is working, you have to do also for the inputs something like this.

CALL "PNIO_SEND" (
CPLADDR:= W#16#100,// Hex Address of the CP 343-1EX21
LEN:= 28,// Number of bytes of the Outputs
IOCS:= P#DB1.DBX 1 .0 BYTE 4,// Status, per byte one bit (28 byte --> 4 byte)
DONE:= DB1.DBX 0.0,// Status Done
ERROR:= DB1.DBX 0.1,// Status Error
STATUS:= DB1.DBW 2,// Statusword
CHECK_IOCS:= DB1.DBX 0.2,// 0:Ok, 1:there is at least one byte not transfered
SEND:= P#DB1.DBX 10.0 BYTE 28);// Output that have to be written to the station

If you push <F1> when you on the FC11 "PNIO_SEND"then you get the help of the block. Also on FC12 "PNIO_RECV" from the "SIMATIC_NET_CP" library you get the help when you push on <F1> {windows help}.

Please consider that youneed a newer STEP7 to do this, I think about minimal V5.3 SP1.

well with the CPU 317 it may work, but I would check the details of the configuration with the Manual of the CPU or the Catalogue. I would even recommend for such large Systems the use of a CPU 319.
I just wonder how you want to achieve to get 6500 Bytes of I/O on one PN IO System? If you want to use additional CP’s than you have to use PNIO_SEND / PNIO_RECV again... I am sorry.

Best regards