Table of Contents
Advertisement
14 •
750-651 (/xxx-xxx) [TTY-Interface 20mA Current Loop]
Datatransfer
TA
RR
IA
BUF_F
IL 0,
IL 1,
IL 2
0
2.1.1.9
Datatransfer
With the control and status byte the controlling of the sending and receive
mode takes place. Requests are indicated by a bit change of state. An assigned
bit indicates execution by adopting the value of the request bit.
Initialization of the module:
• Set IR bit in the control byte
• Initialization of the module
• Transmit/receive functions are blocked
• Output/input buffers are erased
• Serial interface module will load its configuration data
Transmitting data:
• TR=TA: put characters into output bytes
• Amount of characters is specified in OL0 to OL2
• TR is inverted and read out
• Characters are put into output buffer if TR=TA
Receiving data:
• RR≠RA: data in input bytes characters are available
• Amount of characters is specified in IL0 to IL2
• Characters in IL0 to IL2 are read out
• RA is inverted and read out
• All characters are read when RR=RA
Bit 7
Bit 6
Bit 5
0
IL 2
IL 1
Transmit acknowledge
Receive request
Initialization acknowledge
Buffer full
Input length (number of received characters , which have been stored in the
input data)
Constant value must always be 0.
Status byte
Bit 4
Bit 3
Bit 2
IL 0
BUF_F
IA
Bit 1
Bit 0
RR
TA
WAGO-I/O-SYSTEM 750
Busklemmen
Advertisement
Table of Contents
