Example - WAGO 750-651 Manual

The transmitting and receiving of data can be done simultaneously. The
initialization request has priority and will stop transmitting and receiving of
data immediately.
Attention
Resetting the initialization bit can be performed with the following message.
Message: input buffer full (Bit 3)
Input buffer is full. Data which is being currently received is now lost.

2.1.1.9.1 Example

The module is initialized.
The initialization bit in the control byte is set.
After the initialization has been executed, the status byte will give back
000.0100.
Sending of the data string "Hello"
The first 3 characters and the buffer length of 3 are transmitted.
The transmission request bit (TR) is inverted.
WAGO-I/O-SYSTEM 750
Busklemmen
750-651 (/xxx-xxx) [TTY-Interface 20mA Current Loop] • 19
Output byte 0
0x00
Input byte 0 Statusbyte
XX '0XXX. X0XX'
XX '0XXX. X1XX'
Output byte 0
"H" (0x48)
Output byte 0
"H"
Control byte Output byte 2
'0000.0100'
Input byte 2
XX
XX
Control byte Output byte 2
'0011.0000'
Control byte Output byte 2
'0011.0001'
Datatransfer
Output byte 1
0x00
Input byte 1
XX Module is still being
XX Initialization
completed.
Output byte 1
"1" (0x6C) "a" (0x60)
Output byte 1
"1"
0x00
reset.
"a"