Technical data

RS232,TTY,RS485 750-650,651,653

:$*2Ç,2 Ç6<67(0

The PLC is able to control transmission and reception of data by means of the control

byte and the status byte.

Initialization of the module:

• set IR in the control byte

• 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 byte 0 to 2

• 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: in input byte 0 to 2 characters are available

• amount of characters is specified in IL0 to IL2

• charactersin IL0 to IL2 are read out

• RA is inverted and read out

• all characters are read when RR=RA

The transmitting and receiving of data can be done simultaneously. The initialization

request has prioirity and will stop transmitting and receiving of data immediately.

Message: input buffer full (Bit 3)

Input buffer is full. Data which are received now are lost.