How is ASIC VHDL coding different from FPGA VHDL coding?

[shiva_mag]

hi
how is ASIC vhdl coding is diffrent from FPGA vhdl coding?
shiva

 

[fivaro1]

Re: asic vs fpga

VHDL language is the same for both of them.
1) Perhaps the question should be which constructions are supported by the synthesis tool I use, which can limit my coding style. Or...
2)do I prefer very behavioral coding versus low level structural coding: in first case code can be portable but, in last case, if you make calls to library components sure code is not portable.
3) If you use "hard" FPGA components like memories, PLLs, multipliers... or similar specific libraries, this part of code is not "portable" in the sense you are calling components that will not exist in the other technology. So, if you instance specific components, code is not portable, but if you can avoid use them (infering memories, multipliers... in the cases where designs permits it, of course) code will be more portable, but also less fast, of course.

Hope this helps.

 

[earnest_zhl]

Re: asic vs fpga

I think this question may have some relationship to the difference between ASIC and FPGA. for example in FPGA coding you can call FPGA macro module and in asic you can call designware.

another example is when you writing interface for memory, the timing is different in two conditions.

mostly they may have no big difference. I think

 

[yeewang]

asic vs fpga

read the manual of ur particular fpga, focus on the special structures in it.
pay attention to ur coding whenever u're trying to use some kinda structures which can be implemented by tese special structures in fpga.
pay attention to ur memory instantiation.
nothing more.

 

[intel]

Re: asic vs fpga

nowdays FPGAs are becomming more prominent in chip design industry for making first prototye and testing designs.

 

[1011]

Re: asic vs fpga

In my experience, if you have a big production several thousands of pieces may be better the asic but for more limited quantity is better fpga.

 

[Beetroots]

Re: asic vs fpga

Nobody has mentioned the DFT issues. In the ASIC world DFT considerations are extremely important.

 

[zyphor]

Re: asic vs fpga

I think the question should be modified as the topic of

Design difference between ASIC & FPGA.

 

[iamsun]

asic vs fpga

Two difference:
1. In coding, different synthsis directive.
2. In test, manufacture default can be ignored in FPGA based design.

 

[hoangthanhtung]

Re: asic vs fpga

The main differents between ASIC and FPGA is that :
FPGA is semi-custom. It is base LUT (LUT is small sysem which can execute all basic logic funtions. When you design system in FPGA you can waste much resource (LUT) than is necessary.
ASIC is full-custom. You have to optimize your design before deliver design to fabrication. It take much time to complete ASIC design than FPGA design

For this reason, we can consider ASIC = FPGA is optimized

 

[eternal_nan]

asic vs fpga

Coding for every FPGA architecture should be individually thought out in order to fit the structure of logic elements, flip-flops and routing available in that FPGA. Of course, you can just write generic HDL without any consideration for the above, but the quality of results will be drastically poorer. FPGA's are a lot more sensitive to coding style due to comparatively low amount of "building blocks" available to synthesis in comparison to ASIC (lut, FF, routing versus. 2,3,4,6 input AND,OR,XOR,MUX, full adder, half adder, multiple types of flops etc. available in ASIC libraries).

 

[dynoboy]

Re: asic vs fpga

Wow,
ASCI vs FPGA this is really a debatable topic, if cost involved and the volume of production os not an issue.
In FPGA you need not really worry about your timing and layout, theat the work of the Synthesis tool. Alsopower relted heating problems (hot spots) and all is not a major concern.
So for prototyping and testing purposes you prefer FPGA...focus is on getting things to work.

But once the FPGA prototyping is done and the production moves into Mass Production you need to start worrying about the layout of the IC so there are many algos for the same. then you have too many testing phases such as STA (static timing analysis) where the functionality is not tested onlt the design is tested for the desired clocks. There are a lot many other terms associated with the same...

Thats all, more info can be got from the great search engine thats Google

 

[joc_06]

asic vs fpga

In my opinion the main difference is cost and flexibility - fpga's are more suited to design phase not full producxtion runs

 

[AlexWan]

Re: asic vs fpga

FPGA...focus is on getting things to work.

I agree it.
I think FPGA is focus on function. But ASIC pays its attention to the Timing and Area, even Power, Datapath, DFT. So after simulation we can finish the FPGA, but there are many steps for finishing the ASIC: Simulation, STA, Conformal, etc.

 

[gerade]

Re: asic vs fpga

FPGA some serves as an touchable verification for design.

and when time to market is important, FPGA also offer fast deliver to customer.