Bradley Smoker PLC-5 Programming Discrete Transfers Adapter Mode, Data to an Adapter Channel

7-10Communicating with a PLC-5 Adapter Channel

Programming Discrete

Transfers

in Adapter Mode

Typically, each output instruction in one controller should have a corresponding input instruction in the other controller. The rack number of the adapter mode controller-channel determines the addresses that you use.

	Supervisory Processor (PLC-5)						Adapter-mode Processor Channel
			0:x7			N51:15				N51:15
				17	8		9	11	13	15
I:x5		I:x5							N51:05
13	17	16								14

N51 is the adapter-mode processor's discrete transfer configuration file. Input destination and output source entries determine input and output words.

The ladder logic in the supervisory processor uses the rack number of the adapter-mode processor channel.

Condition the ladder logic in the adapter processor with the status bits (page ).

Programming Block-Transfers

of Data to an Adapter Channel

Adapter-mode block-transfers are essentially continuous. As soon as a transfer is completed, another block-transfer occurs immediately in the adapter-mode controller; it then waits (with a buffered snap-shot of data) for the supervisory controller to perform another block-transfer request. Therefore, the data that is transferred after the request is data from the previous transfer. If the supervisory controller performs a block-transfer request from the adapter-mode controller every 500 ms, for example, the data is at least 500 ms old.

The supervisory controller contains the ladder-logic transfer instructions which controls the actual communication transmission. However, the adapter-mode controller channel controls the:

•actual number of words of data that is transferred

•data table location from which the data is transferred

	Do not use ladder-logic block-transfer instructions for the
IMPORTANT
	adapter-mode controller channel; you configure the
	block-transfers from channel configuration screens and
	data monitor screens.

Publication 1785-UM012D-EN-P - July 2005