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558 Discussions

About 10bitsPerSymbol of ihc::stream_out

ZXued
Beginner
546 Views

I want to use ihc::stream with 10bitsPerSymbol parameter, I defined a interface using:

typedef ihc::stream_out<ac_int<120, false>, ihc::buffer<2>, ihc::readyLatency<1>, ihc::usesPackets<true>, ihc::bitsPerSymbol<10>, ihc::usesEmpty<true>, ihc::firstSymbolInHighOrderBits<true>>  stream_out_pixels;

 

When compiling, the compiler report following error:

_stream.h:769:54: error: HLS builtin parameter must be a factor of the type size

                   _readyLatency, _bitsPerSymbol,

How can I use 10bitsPerSymbol stream interface.

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4 Replies
AnilErinch_A_Intel
503 Views

Hi ,

As per the compiler pro documentation

ihc::buffer can be used only with the input stream,

Please refer to the compiler pro documentation

https://www.intel.com/content/www/us/en/programmable/documentation/ewa1462824960255.html

for each of the options in the code given and let us know the results.

Thanks and Regards

Anil

 

ZXued
Beginner
503 Views

Thanks for you replay, I remove ihc::buffer on output stream but the problem isn't been solved. I think the result of express "sizeof(ac_int<120, false>)" is not divisible by 10

AnilErinch_A_Intel
503 Views

Hi ,

Can you try with different ac_int values and lets know , whether the compilation gets successful , when the result is divisible by 10 .

Thanks and Regards

Anil

whitepau
Employee
462 Views

Hi @ZXued 

There is currently a restriction on `ihc::bitsPerSymbol` such that symbol widths must be a power of 2. This is a known issue.

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