Bradley Smoker PLC-5 user manual Optimizing Instruction Execution Time and Controller Memory

4-22Addressing I/O and Controller Memory

Optimizing Instruction Execution Time and Controller Memory

TIP

For the best instruction-execution performance, store your most frequently used addresses as shown below:

Address bit instructions between the end of the input image file and physical word 256. Bit addresses located in words greater than 256 require one extra word in the controller's memory for storage and execute 0.16ms slower than bit addresses stored in words 0-255.

Address element instructions between the end of the input image and physical word 2048. Addresses stored in words greater than 2048 require more words in the

controller's memory for storage.

	PLC-5/11,		PLC-5/30	PLC-5/40, -5/40L		PLC-5/60, -5/60L		File Type
-5/20, -5/20E		Physical Word #			-5/40E	-5/80, -5/80E			Default File #
Physical Word #				Physical Word #		Physical Word #
0-31		0-63		0-127		0-191		output image 1	0
frequently
used bit
addresses		32-127		32-255		32-383		input image 1	1
32-63
			word 256
								binary, timer, counter, control,
									3-999
frequently								integer, floating point
									according to your
used			word 2048						application
element								block transfer, message, PID,
addresses								SFC status, ASCII string
								status 2	2
							1 The minimum size of the file is 32 words.
							2 The status file is always the last physical file in the data table.

Publication 1785-UM012D-EN-P - July 2005