Siemens SIMATIC TIWAY 1 - Manual (Page 36)

OPERATION AND APPLICATION
UNILINK HOST ADAPTER 2–26
USER MANUAL
2.9.2 Sending Data To And From Secondary Devices
After the secondary device is connected, your applications software can send
TIWAY I Primitives to the secondary with the SEND NETWORK DATA
command or the BROADCAST NETWORK DATA TRANSFER command. The
TIWAY I Primitives provide control functions such as reading and writing data
elements, controlling the operating mode, and testing the status and
configuration of the secondary devices.
The SEND NETWORK DATA command transfers a TIWAY I Primitive to a
specified secondary device. When completed, the adapter will return the
command code, the secondary address, and the Primitive response.
NOTE
The host computer must wait for the response to be
returned for the SEND NETWORK DATA and
BROADCAST NETWORK DATA commands before
issuing another command, regardless of adapter’s
operating mode.