Agilent Technologies 2948, 2712A manual Schematic Diagram Notes 7

Service Model 8904A

Table 8-1.Schematic Diagram Notes (7 of 11)

DIGITAL SYMBOLOGY REFERENCE INFORMATION

	Sequential Logic	Functions (Cont’d)
REG	Register-Array	of unconnected flip-flops that form a simple register or latch.
SREG	Shift Register-Array of flip-flops that form a register with internal connections that
	permit shifting the contents from flip-flop to flip-flop.
ROM	Read Only Memory-Addressable				memory with read-out capability only.
RAM	Random Access Memory-Addressable memory with read-in and read-out
	capability.
	Dependency Notation
Crn	Control Dependency-Binary			affecting input used where more than a simple AND
	relationship exists between the C input and the affected inputs and outputs (used
	only with D-type flip-flops).
Gm	Gate (AND) Dependency-Binary				affecting input with an AND relationship to those
	inputs or outputs labeled with the same identifier. The m is replaced with a number
	or letter (the identifier).
Vm	OR Dependency-Binary		affecting input with an OR relationship to those inputs or
	outputs labeled with the same identifier. The m is replaced with a number or the
	letter (the identifier).
mAm	Address Dependency-Binary			affecting inputs of affected outputs. The m prefix is
	replaced with a number that differentiates between several address inputs, indicates
	dependency,or indicates demultiplexing of address inputs and outputs. The m suffix
	indicates the number of cells that can be addressed.
ENm	Enable Dependency-Binary			affecting input which, when active enables all outputs.
	When inactive open-collector and open-emitter outputs are off, and three-state out-
	puts are at an external high impedance state.
	When the enable input affects only certain inputs and outputs, they will be numbered
	to indicate the logic connection.
Xm	Transmission Dependency-Binary				affecting input which bidirectionallyconnects de-
	pendent inputs and outputs.
Mm	Mode Dependency-Binary		affecting input used to indicatethat the effects of partic-
	ular inputs and outputs of an element depend on the mode in which the element
	is operating. The m is replaced with a number or letter (the identifier).
Zm	Interconnection Dependency-Indicates the existence of internal logic connections
	between inputs, outputs, internal inputs, and/or internal outputs. The m is replaced
	with a number (the identifier).
	Comma-AND	Function.
I	Slant-OR Function.				NOTE

The identifier (m) is omitred if it is one-that is, when there is only one depen- dency relationship of rhat kind in a particular device. When this is done, the de- pendency indicator itself (G,C, EN, or V) is used to prefix or suffix the affected (dependent) input or output.

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