13-10-2012, 04:49 PM
Study on VHDL & its Application
VHDL PPT.ppt (Size: 902.5 KB / Downloads: 49)
Introduction to VHDL
VHDL is an acronym of VHSIC Hardware Description Language
VHSIC is an acronym of Very High Speed Integrated Circuits.
VHDL is a programming language that allows one to model and develop complex digital systems in a dynamic envirornment.
Important:
the VHDL is standardized for system specification
but not for design
Features of VHDL
Support for concurrent statements
- in actual digital systems all elements of the system are active simultaneously and perform their tasks simultaneously.
Library support
- user defined and system predefined primitives
reside in a library system
Sequential statements
- gives software-like sequential control (e.g. case, if-then-else, loop)
Technology independent
Type declaration and usage
a hardware description language at various levels of abstraction should not be limited to Bit or Boolean types.
VHDL allows integer, floating point, enumerate types, as well as user defined types
possibility of defining new operators for the newtypes.
Timing control
ability to specify timing at all levels
clocking scheme is completely up to the user, since the language does not have an implicit clocking scheme
constructs for edge detection, delay specification, ... etc are available.
Applications of VHDL
Hardware design
ASIC: technology mapping
FPGA: CLB mapping
PLD: smaller structures, hardly any use of VHDL
Standard solutions, models, behavioural description, ...
Software design
VHDL - C interface (tool-specific)
Main focus of research (hardware/software co-design)
Model and document digital systems
Different levels of abstraction
Behavioral, structural, etc.
Verify design
Synthesize circuits
Convert from higher abstraction levels to lower abstraction levels