Free Stuff

• Doulos HDL Associates  
• ALDEC, Inc.
• The course written by John Sanguinetti.

Free Simulators

• GPL Cver from Pragmatic C Software  
• Verilogger Pro from SynaptiCAD Inc. (previously veriwell of Wellspring) Linux Binary
• Icarus  , Icarus Windows Binaries 

Free Waveform Viewer

• GTKWave Electronic Waveform Viewer  

The TimingAnalyzer can be used to draw timing diagrams of digital interfaces and check for timing problems in digital system designs. Signals, clocks, buses, delays, constraints, states, logic gates, counters, and shift registers are easily added from the gui. Visit http://www.timinganalyzer.net/ for download.
 

Free VHDL to Verilog RTL translator

Vincenzo Liguori has released a VHDL to Verilog RTL translator under GPL. Although limited, this program correctly translated his Triple DES and JPEG cores. It is based on YACC/ C and it has been tested on Linux and Sun. You can fetch it at our download page:
http://www.ocean-logic.com/downloads.htm

Free IP Cores

• http://www.young-engineering.com/intellectual_property.html 
• http://www.free-ip.com/

ASIC and FPGA Cores for the masses.
The current Free-IP cores are:
1. Free-DES -- A DES encryption/decryption engine.  Over 363 megabytes/second in an FPGA!(VHDL)
2. Free-6502 -- An 8-bit micro controller that is software compatible with the standard 6502.(VHDL)
3. Free-RAM -- A portable and parameterized RAM core, including FIFO's and dual port RAM's.(VHDL)
4. Free-RISC8 -- An 8-bit micro controller that is binary compatible with another popular CPU.(Verilog, plus experimental VHDL)
5. Free-LIB1 -- A library of NCO, DAC, and PWM parameterized cores in VHDL, plus software to analyze the frequency spectrum of their outputs.
6. Free-CORDIC -- The CORDIC (COordinate Rotation Digital Computing) core.
• http://www.opencores.org/

Freely available IP cores like Mini-RISC CPU/Microcontroller, compatible with the PIC 16C57 from Microchip
 
• Free Memory Cores

http://www.geocities.com/SiliconValley/Pines/6639/ip/memory_cores.html
 
• http://www.estec.esa.nl/wsmwww/erc32/

European Space Agency developed their own ERC32 which is a radiation-tolerant SPARC V7 processor developed for space applications. Loads of information is available from this site.
• http://www.cmosexod.com/freeip.htm 

Jeung Joon Lee  maintains this site with free  cores for 12bit DSP core and             peripherals, 8 bit CISC processor, Self contained "single-chip" frequency counter, SDRAM Controller etc.