Bradley Smoker PLC-5 Process Control, Message Instructions, Block Transfer Instructions

Instruction Set Quick Reference D-25

Process Control, Message Instructions

Instruction					Description
				Proportional, Integral,	The control block (PD10:0) contains the instruction information
		PID
	PID			and Derivative	for the PID. The PID gets the process variable from N15:13 and
				PID	sends the PID output to N20:21. The tieback stored in N15:14
	Control Block		PD10:0
					handles the manual control station.
	Proc Variable		N15:13	Status Bits:
	Tieback		N15:14
				EN - Enable	If you use an N control block, the rung must transition from
	Control Output		N20:21
				DN - Done Bit (for N	false to true for execution.
				control blocks only)	If you use PD control block, then there is no done bit. Also, the
					rung input conditions need to be true.
					See page F-8 for a description of prescan operation for
					this instruction.
					If the input conditions go from false to true, the data is
		MSG
					transferred according to the instruction parameters you set
	SEND/RECEIVE MESSAGE
					when you entered the message instruction. The Control Block
	Control Block		MG7:10		(MG7:10) contains status and instruction parameters.
					You can also use N control blocks.
	Bit #Status Bits
	15EN - Enable				For continuous MSGs, condition the rung to be true for only one
	14ST - Start Bit
	13DN - Done Bit				scan.
	12ER - Error Bit				See page F-8 for a description of prescan operation for
	11CO - Continuous
	10EW - Enabled-Waiting				this instruction.
	9NR - No Response

Block Transfer Instructions

Integer (N) control block Block Transfer (BT) control block

Word

Offset Description

0status bits (see below)

1requested word count

2transmitted word count

3file number

4element number

Word 0

Word
Mnemonic	Description
.EN through .RW	status bits
.RLEN	requested length
.DLEN	transmitted word length/error code
.FILE	file number
.ELEM	element number
.RGS	rack/group/slot

15	14	13	12	11	10	09	08	07	06	05	04	03	02	01	00
EN	ST	DN	ER	CO	EW	NR	TO	RW	** rack	**	**	group**		slot

Publication 1785-UM012D-EN-P - July 2005