//// ac51_daa.v//// ac51 microcontroller core//// Version 0.6//// Copyright 2008, Hideyuki Abe. All rights reserved.// Distributed under the terms of the MIT License.//module ac51_daa(	in,	cy_bit,	ac_bit,	out,	new_cy);input [7:0]	in;input	cy_bit;input	ac_bit;output [7:0]	out;output	new_cy;wire	vld_l;wire	vld_h;reg [7:0]	da_reg;assign	vld_l = (in[3:0] <= 4'h9);assign	vld_h = (in[7:4] <= 4'h9);always @(vld_l or vld_h or cy_bit or ac_bit or in) begin	if(cy_bit) begin		if(ac_bit) begin			da_reg = 8'h66;		end		else begin			if(vld_l) da_reg = 8'h60;			else da_reg = 8'h66;		end	end	else begin		if(ac_bit) begin			if(vld_h) da_reg = 8'h06;			else da_reg = 8'h66;		end		else begin			if(vld_l) begin				if(vld_h) da_reg = 8'h00;				else da_reg = 8'h60;			end			else begin				if(in[7:4] <= 4'h8) da_reg = 8'h06;				else da_reg = 8'h66;			end		end	endend	// always// resultassign	out = in + da_reg;// carryassign	new_cy = (da_reg[7:4] == 4'h6);endmodule// End of ac51_daa.v