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researchv10 Dan Cross
.so CDL .TH PINS 1G .SH NAME pins \- look up pin names .SH SYNOPSIS .B pins .I pattern ... .SH DESCRIPTION .I pins prints the description of the chip type .I pattern from the file .BR /usr/lib/cda/lib/pins . .I pattern is in a form suitable for .IR grep (I). If the name matched is a synonym for another part, both type names will be printed. The pin names and pin numbers are used by the circuit macro expander .IR cdm . .sp.5 .SS Naming Conventions .PP A set of pin naming conventions is used, based on the traditional naming found in, for example, the Texas Instruments TTL Data Book. Function inputs and outputs are usually given as a single capital letter. Special inputs and outputs are given a short mnemonic name, such as \fBCLR\fP for clear. Lowercase letters are used where a subscript might normally be used. Where multiple gates exist within a single package, they are distinguished by appending a zero based numeric index. Pins which are active when low are indicated by adding a minus sign as the last character of the name. .LP General inputs are labeled with a single letter starting with the letter .BR A . Functions with single inputs use the letter .B D with indices, as well as memories and flip-flops. When the outputs of logic elements are not synchronous with respect to another input they are named .BR Y . Synchronous outputs, such as with flip-flops are called .BR Q . Clock lines are called .BR CK , clear lines are called .BR CLR , preset lines are called .BR PR . Select lines for multiplexors and data selectors are called .BR S . The letter .B G is used for enable, chip enable, chip select, and output enable. The use of .B OE for output enable is used for tri-state devices where there is a separate enabling of the chip and its outputs (such as 74S373). Memories use the letter .B A for address lines, .B WE for write enable and .B Y for outputs. \*(SA
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