Bradley Smoker PLC-5 Addressing Summary, Addressing Block-Transfer Modules, To Address Use

Addressing I/O and Controller Memory 4-7

Addressing Block-Transfer Modules

Block-transfer modules occupy 8 bits in the controller’s I/O image table. Since all block-transfer modules are bidirectional, they cannot be used to complement either input or output modules.

To Address	Use
single slot modules	assigned I/O rack and group number of the slot in which the
	module resides and 0 for the module number
	When using 1/2-slot addressing, use the assigned rack
	number and the lowest group number and 0 for the module
	number.
double-slot modules	assigned rack number and the lowest group number and 0 for
	the module number

Addressing Summary

Use this table as a quick reference for addressing.

Addressing
Mode	Guidelines
2-slot	• Two I/O module slots = 1 group
	• Each physical 2-slot I/O group corresponds to one word (16 bits) in the input image table and
	one word (16 bits) in the output image table
	• When you use 16-point I/O modules, you must install as a pair an input module and an output
	module in an I/O group; if you use an input module in slot 0, you must use an output module in
	slot 1 (or it must be empty). This configuration gives you the maximum use of I/O.
	• You cannot use a block-transfer module and a 16-point module in the same I/O group because
	block-transfer modules use 8 bits in both the input and output table. Therefore, 8 bits of the
	16-point module would conflict with the block-transfer module.
	• You cannot use 32-point I/O modules.
	• Assign one I/O rack number to eight I/O groups.
1-slot	• One I/O module slot = 1 group
	• Each physical slot in the chassis corresponds to one word (16 bits) in the input image table and
	one word (16 bits) in the output image table
	• When you use 32-point I/O modules, you must install as a pair an input module and an output
	module in an even/odd pair of adjacent I/O group; if you use an input module in slot 0, you must
	use an output module in slot 1 (or it must be empty). This configuration gives you the maximum
	use of I/O.
	• Use any mix of 8- and 16-point I/O modules, block-transfer or intelligent modules in a single I/O
	chassis. Using 8-point modules results in fewer total I/O.
	• Assign one I/O rack number to eight I/O groups.
1/2-slot	• One half of an I/O module slot = 1 group
	• Each physical slot in the chassis corresponds to two words (32 bits) in the input image table
	and two words (32 bits) in the output image table
	• Use any mix of 8-, 16-, and 32-point I/O or block-transfer and intelligent modules. Using 8-point
	and 16-point I/O modules results in fewer total I/O.
	• With the controller-resident local rack set for 1/2-slot addressing, you cannot force the input
	bits for the upper word of any slot that is empty or that has an 8-point or 16-point I/O module.
	For example, if you have an 8-point or a 16-point I/O module in the first slot of your local rack
	(words 0 and 1 of the I/O image table, 1/2-slot addressing), you cannot force the input bits for
	word 1 (I:001) on or off.
	• Assign one I/O rack number to eight I/O groups.

Publication 1785-UM012D-EN-P - July 2005