题解 | #使用8线-3线优先编码器Ⅰ实现16线-4线优先编码器#
使用8线-3线优先编码器Ⅰ实现16线-4线优先编码器
http://www.nowcoder.com/practice/dcfa838e43de4744bc976abee96dc566
`timescale 1ns/1ns module encoder_83( input [7:0] I , input EI ,
output wire [2:0] Y ,
output wire GS ,
output wire EO
);
assign Y[2] = EI & (I[7] | I[6] | I[5] | I[4]);
assign Y[1] = EI & (I[7] | I[6] | ~I[5]&~I[4]&I[3] | ~I[5]&~I[4]&I[2]);
assign Y[0] = EI & (I[7] | ~I[6]&I[5] | ~I[6]&~I[4]&I[3] | ~I[6]&~I[4]&~I[2]&I[1]);
assign EO = EI&~I[7]&~I[6]&~I[5]&~I[4]&~I[3]&~I[2]&~I[1]&~I[0];
assign GS = EI&(I[7] | I[6] | I[5] | I[4] | I[3] | I[2] | I[1] | I[0]); //assign GS = EI&(| I);
endmodule
module encoder_164( input [15:0] A , input EI ,
output wire [3:0] L ,
output wire GS ,
output wire EO
);
wire GSH,EOH,GSL,EOL;
wire [2:0] YH,YL;
encoder_83 e83h(
.I(A[15:8]),
.EI(EI),
.Y(YH[2:0]),
.GS(GSH),
.EO(EOH)
);
encoder_83 e83l(
.I(A[7:0]),
.EI(EI & (EOH)),
.Y(YL[2:0]),
.GS(GSL),
.EO(EOL)
);
assign L[3]=EI & (GSH);
assign L[2:0]=(L[3])?(YH[2:0]):(YL[2:0]);
assign GS=GSH | GSL;
assign EO=EOH & EOL;
endmodule
