Synthesis

[onkarkk1]

Hi ,

While doing synthesis of my design im getting following error:::::

Xst:2636 - "f3.v" line 32: Loop has iterated 10000 times. Use "set -loop_iteration_limit XX" to iterate more. 

i have tried setting loop iteration limit using tcl console but no use....

I am using ISE 10.1.3 on debian(lenny)..

could any one please help me ......

regards

Krishna Kishore 

[onkarkk1]

hi sorry,

i got the solution ...

regards

Krishna Kishore 

[onkarkk1]

add -loop_iteration_limit  XX    XX may be any number depends on ur loop count in the .xst file in ur project folder and compile it will work....

[bassman59]

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onkarkk1 wrote:
add -loop_iteration_limit  XX    XX may be any number depends on ur loop count in the .xst file in ur project folder and compile it will work....

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I would worry about this error and changing this limit. It usually means something bad.

[onkarkk1]

As i have learnt , the tool has default limit of 64 for loop count ( any loop) , if it execeeds that then it will give this error, to over come this one has to set this attribute in .xst file.

Please correct me if i am wrong.

regards

Krishna Kishore

[bassman59]

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onkarkk1 wrote:

As i have learnt , the tool has default limit of 64 for loop count ( any loop) , if it execeeds that then it will give this error, to over come this one has to set this attribute in .xst file.

Please correct me if i am wrong.

regards

Krishna Kishore

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I don't know what the actual limit is, but this is the sort of error you get when you synthesize a big combinatorial loop.

[shazni]

Hello onkarkk1

I also have the same problem now. You have post this thread in last year. You have said you solved it. I also understand that I need to add  set -loop_iteration_limit XX in .xst file in project folder. In my case XX should be 32768 iteartions. I did it so. But still the same issue. 

I need a bit descriptive answer from you. It's really urgent. It be very mush appreciable if you can explain me this in case I'm doing some silly mistake. Do I need to append just the above line in the .xst? What else I need to do?

[onkarkk1]

might be u r using gui for compilation , if that is the case as i remember it didnt work for me too , more over it will overwrite your settings. Actually i have used a script for compilation, i.e., xst manual there u will get for  every procees there will be a command based on that i have written a script and it worked for me..

regards

krish 

[shazni]

Thank you onkarkk1

Thanks. Sorry for the late reply. I was on leave. Anyway I solved the issue in another way. In fact it's not a method. This error comes, because  'for loop exceeds the limit. I still didn't solve for 'for' loop. I omit the for loop, since I really don't want an initialization process as I'm not gonna use the initial values in my algorithms. For loops are mostly used in initialization rather than for the algorithm itself in Verilog.