Download altmult_add Megafunction User Guide

1. About this Megafunction
Device Family
Support
The altmult_add megafunction supports the following target Altera®
device families:
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Stratix® series
Cyclone® series
HardCopy® series
MAX® series
APEXTM series
ACEX® devices
FLEX® series
Introduction
As design complexities increase, use of vendor-specific IP blocks has
become a common design methodology. Altera provides
parameterizable megafunctions that are optimized for Altera device
architectures. Using megafunctions instead of coding your own logic
saves valuable design time. Additionally, the Altera-provided functions
may offer more efficient logic synthesis and device implementation. You
can scale the megafunction’s size by simply setting parameters.
Features
The altmult_add megafunction implements a basic adder/multiplier and
offers many additional features including:
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General
Description
Parameterizable input data and output data widths
Active high asynchronous clear and clock-enable control inputs
Support for both signed and unsigned data representation formats
Ability to add or subtract the product pair
Facility to added extra latency to have additional registers required
to pipeline the output of the multiplier/adder
The altmult_add megafunction allows you to implement a
multiplier/adder. A multiplier/adder accepts pairs of inputs. The
members of each pair are multiplied together and the multiplier/adder
then adds or subtracts the products of all other pairs. This function can be
expressed as an equation (Equation 1).
(1)
y = A 0 B 0 ± A 1 B 1 ± …± A n B n
In this equation, n denotes the number of pairs.
Altera Corporation
March 2007
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altmult_add Megafunction User Guide