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Altera_Forum
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14 years ago

Counting the position of ones in a binary vector

I want to design a combinatorial circuit for an fpga which will count the position of ones in a 16 bit vector. eg1 if vector is 16'b0000_0000_0011_0101 then output should be 64'h0000_0000_0000_5...
Altera_Forum's avatar
Altera_Forum
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14 years ago

This will not be straightforward to realise in a combinatorial circuit because what you describe is a rather sequential process: traverse the input vector from right to left, if you encounter a bit set to '1' add its position index into the next available output slot.

This doesn't mean it can't be done combinatorially, but the result will be huge as it has to cater for all combinations (all 65356 of them ...).