Difference between LUTs from Xilinx and Altera

[ikru26]

1) A single ALM has max of 8 input

ie 2 LUTs or ALUTs

either it can have same size or different size.

eventhough the max input is 8 we are using only 7 inputs in all the cases .

2) can anyone tell me some differences between @ltera ALM and what is the equivalent in Xilinx. ( ALM_ Adaptive logic Module ).

3) Difference between

1) LUTs in Xilinx and @ltera
2) DLL's and PLL's
3) Architecture wise between Stratix ii and Virtex 4


3) what are the major differences in @ltera FPGA mainly Stratix II with Xilinx Virtex -4 pro

 

[naaj_ila]

Re: Xilinx and Altera

check out this altera pdf

 

[nxtech]

Re: Xilinx and Altera

Just curious but I have to ask, why does it matter what the differences are between the Xilinx and Altera devices?

E

 

[abhikohli]

Xilinx and @ltera

@nxtech
IMHO Though one can say that when we are writing or using (in case of purchased IPs) tech. independent HDLs for designing and relying on synth tools for tech. mapping why do we need to know the difference between the archs . However, knowing the arch. of the tech you are going to use is extremely important for doing a efficient design and for optimization. Moreover, especially in FPGA designs you must know what are the available resource for you to use and their limitations. In many cases you may need to instantiate a component rather then inferring it in synth. for which you must have arch. knowledge.
Am I right here ?