dpmlt032m.vmd
3.45 KB
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/**************************************************************/
/* Verilog module of datapath cell dpmlt032m */
/* Designed by Lin Yang VLSI Technology Jan. 25, 91 */
/* Designed by Chunling Liu Compass June 16, 92 */
/* Edited by Paul Hyland Compass Feb. 10, 93 */
/* */
/* The following is the port description */
/* Data ports */
/* X : the input port */
/* Y : the input port */
/* MSB : the output port */
/* LSB : the output port */
/* Control ports */
/* INST_CP : the clock signal */
/* Parameters */
/* WORDSIZE : the word size of the datapath cell */
/* Y_Bus_Size : the Y input width (also known as the */
/* number_of_columns */
/* unsigned : the unsigneded boolean/2's complement */
/* number_of_pipes : the number of pipeline statge */
/* DELAY : the delay time from input to output */
/**************************************************************/
module dpmlt032m(X, Y, MSB, LSB, INST_CP);
parameter WORDSIZE = 8, Y_Bus_Size = 8, unsigned = 1, number_of_pipes = 1, DELAY = 30, BF = 1;
input [WORDSIZE-1:0] X, Y;
output [WORDSIZE-1:0] MSB, LSB;
input INST_CP;
reg [WORDSIZE-1:0] MSB, LSB;
reg [WORDSIZE-1:0] px[1:number_of_pipes];
reg [Y_Bus_Size-1:0] py[1:number_of_pipes];
reg [WORDSIZE-1:0] tx[1:number_of_pipes];
reg [Y_Bus_Size-1:0] ty[1:number_of_pipes];
reg [WORDSIZE-1:0] ix, sx;
reg [Y_Bus_Size-1:0] iy, sy;
reg [WORDSIZE+Y_Bus_Size-1:0] Z;
task mlt;
integer n;
begin
// update pipeline registers
tx[1] = X;
ty[1] = Y;
for (n=2; n<=number_of_pipes; n=n+1)
begin
tx[n] = px[n-1];
ty[n] = py[n-1];
end
if (unsigned == 0)
begin
ix = tx[number_of_pipes];
iy = ty[number_of_pipes];
if (ix[WORDSIZE-1] ^ iy[Y_Bus_Size-1])
begin
if (ix[WORDSIZE-1] == 1)
begin
sx = ~ix + 1;
sy = iy;
end
else if (iy[Y_Bus_Size-1] == 1)
begin
sx = ix;
sy = ~iy + 1;
end
Z = ~(sx * sy) + 1;
end
else if (ix[WORDSIZE-1] ^~ iy[Y_Bus_Size-1])
begin
if (ix[WORDSIZE-1] == 0)
begin
sx = {1'b0, ix[WORDSIZE-2:0]};
sy = {1'b0, iy[Y_Bus_Size-2:0]};
Z = sx * sy;
end
else
begin
sx = ~ix +1;
sy = ~iy +1;
Z = sx * sy;
end
end
else
Z = {WORDSIZE+Y_Bus_Size{1'bx}};
end
else
Z = tx[number_of_pipes] * ty[number_of_pipes];
#DELAY update;
end
endtask
task update;
integer n;
begin
for (n=1; n<=number_of_pipes; n=n+1)
begin
px[n] = tx[n];
py[n] = ty[n];
end
// do the multiplication
LSB = {{WORDSIZE-Y_Bus_Size{1'b0}},Z[Y_Bus_Size-1:0]};
MSB = Z[WORDSIZE+Y_Bus_Size-1:Y_Bus_Size];
end
endtask
always @(posedge INST_CP) mlt;
endmodule