Transmission Channel; Figure 48 Use Of The Handshake Byte - WAGO 750 Product Manual

Appendix

8.2.2 Transmission Channel

To transfer a message over a narrow channel, synchronization between sender and re-
ceiver is required. Therefore, the transmission channel is divided into a synchronization
part and a data part.
For synchronization, a so-called handshake byte (HB) is defined. The handshake byte oc-
cupies the first byte of the transmission channel while part of the message is always de-
livered in the remaining bytes.
HB
There is always one transmission channel from the sender to the receiver and one trans-
mission channel from the receiver to the sender. Both channels do not have to be the
same size. However, the minimum size is 1 byte.
Handshake Byte
In general, a distinction is made between Control (C) and Toggle (T) mode (bit 7). The C
mode is used to synchronize the subscribers. The T mode is used to exchange data.
Structure of the handshake byte:
Bit 7
C/T
The following figure shows the basic use of the handshake byte.
78 Product manual | Version: 1.1.0
Proportional Valve Module 2-3-4
Bit 6 Bit 5 Bit 4
Status
Response
T 0x0
Part of the message
Bit 3 Bit 2
Control
C/T Command
T
Figure 48: Use of the Handshake Byte
750-1632/000-100
Bit 1 Bit 0
0x0