Process image

Complex mapping

In the complex process image the KL2542 is represented with at least 6 bytes of input data and 6 bytes of output data. These are organized as follows:

Byte offset (without word alignment)	Byte offset (with word alignment*)	Format	Input data	Output data
0	0	Byte	SB1:	CB1
1	2	Word	DataIN1	DataOUT1
3	4	Byte	SB2	CB2
4	6	Word	DataIN2	DataOUT2

Compact mapping

The KL2542 devices are represented in the compact process image with a minimum of 6 bytes of output data. These are organized as follows:

Byte offset (without word alignment)	Byte offset (with word alignment*)	Format	Input data	Output data
0	0	Byte	-	CB1
1	2	Word	-	DataOUT1
3	4	Byte	-	CB2
4	6	Word	-	DataOUT2

*) Word alignment: The Bus Coupler places values on even byte addresses

Key

SB n: Status byte of channel n
CB n: Control byte of channel n
DataIN n: Input word of channel n
DataOUT n: Output word of channel n

	Control-Bytes The KL2542 cannot be operated without control bytes, since the control bytes are required for enabling the channels. Even if your Bus Coupler is set to compact process image, the KL2542 is represented with its control bytes.