highest_10.inc

本電子檔為 verilog cookbook,包含了通訊,影像,DSP等重要常用之verilog編碼,可作為工程師與初學者的參考手冊

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// helper function to identify
// the most significant bit where upper is 1 and
// lower is 0.

function integer highest_10;
	input integer upper;
	input integer lower;
	integer log2_upper;
	integer j;
	begin
		highest_10 = 0;
		log2_upper = log2 (upper);
		for (j=0; j<log2_upper; j=j+1)
		begin
			if (upper[j] && !lower[j])
				highest_10 = j;
		end			
	end
endfunction