A Question About MULTIPLICATION

[jonatan]

Does someone know what is the difference between using only
the * to do one multiplication with 2 signals (10bits each one)

..." Result <= Sigal_A * Signal_B; "....

and do the same operation using the coregen multiplier block(ISE 6.1i).


Thanks in Advance...

 

[dll_embed]

In virtex II and above, I see no difference in my design. My ise5.2i infer the hardware multiplier.But if your hardware multiplier is not enough, there maybe a difference. I thing by using corgen module, you can determine which one to use hardware multiplier.

regards

 

[pandayeah]

It seems no different.
But if you want to improve the performance of you design , you could use the own MUL module instead.

 

[maestor]

I guess it depends of hoe smart your synthesizer is. I guess Leonardo and Synplify will infer the multiplier just using the '*'.

Using the module generated by Coregen makes your design Xilinx specific and is not a good practice although it guarantees that the blackbox is going to be mapped properly duing the mapping process.

--maestor

 

[pahol]

if you want to improve your design, you can use multiply by CoreGen and set it to the maximux pipeline.

 

[Black Jack]

I think that for improve performance of multiplier you need use
algorythmic approach. For MULTIPLICATION you can use some methods
See **broken link removed** for detail

Also you can download e-book "DSP with FPGA" (after registration)
I haven`t this book. But my collegues advise me for download it.
Lot info for arithmetics in FPGA

www.mcu.cz/atm/index.php?&direction=0&order=&directory=UsersFiles/mhmhmh