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`timescale 1us/1us
`include "alu.sv"
`include "cond_check.sv"
module instruction_decode #(
parameter DATA_WIDTH = 16
) (
input [15:0] instruction,
input [(DATA_WIDTH-1):0] A_i,
input [(DATA_WIDTH-1):0] D_i,
input [(DATA_WIDTH-1):0] pA_i,
output [(DATA_WIDTH-1):0] RES,
output do_jump,
output dst_a,
output dst_d,
output dst_pa
);
assign dst_a = instruction[5];
assign dst_d = instruction[4];
assign dst_pa = instruction[3];
wire use_pointer_a_for_alu;
wire [(DATA_WIDTH-1):0] alu_y;
assign use_pointer_a_for_alu = instruction[12];
assign alu_y = use_pointer_a_for_alu ? pA_i : A_i;
wire [(DATA_WIDTH-1):0] alu_res;
alu #(
.DATA_WIDTH(DATA_WIDTH)
) my_alu (
.X(D_i),
.Y(alu_y),
.u(instruction[10]),
.opcode(instruction[9:8]),
.zx(instruction[7]),
.sw(instruction[6]),
.RES(alu_res)
);
cond_check #(
.DATA_WIDTH(DATA_WIDTH)
) my_cond (
.X(alu_res),
.ltz(instruction[2]),
.eqz(instruction[1]),
.gtz(instruction[0]),
.res(do_jump)
);
assign RES = alu_res;
endmodule
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