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Altera_Forum
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7 years ago

how to share DSP correctly ?

16bit or 8bit multiply should only use 0.5 DSP. I have try to implement two char type MAC, and the result will be store into int type. The DSP usage should be 64x16/2=1024/2=512 and in repo...
Altera_Forum's avatar
Altera_Forum
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7 years ago

You cannot do two MACs per DSPs, regardless of your data size, since each DSP only has one adder. If your data size is smaller than 18 bits, you can do a maximum of two MULs per DSP, or a dot product like "±(ax * ay) + (bx * by)". Refer to the following document for the different modes of computation for each DSP:

https://www.altera.com/en_us/pdfs/literature/ug/ug_nfp_dsp.pdf