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module fsm ( clock, reset, req_0, req_1, gnt_0, gnt_1 );
input clock,reset,req_0,req_1;
output gnt_0,gnt_1;
wire clock,reset,req_0,req_1;
reg gnt_0,gnt_1;
parameter SIZE = 3;
parameter IDLE = 3'b001;
parameter GNT0 = 3'b010;
parameter GNT1 = 3'b100;
parameter GNT2 = 3'b101;
reg [SIZE-1:0] state;
reg [SIZE-1:0] next_state;
always @ (posedge clock)
begin : FSM
if (reset == 1'b1) begin
state <= #1 IDLE;
gnt_0 <= 0;
gnt_1 <= 0;
end
else
case(state)
IDLE : if (req_0 == 1'b1) begin
state <= #1 GNT0;
gnt_0 <= 1;
end else if (req_1 == 1'b1) begin
gnt_1 <= 1;
state <= #1 GNT0;
end else begin
state <= #1 IDLE;
end
GNT0 : if (req_0 == 1'b1) begin
state <= #1 GNT0;
end else begin
gnt_0 <= 0;
state <= #1 IDLE;
end
GNT1 : if (req_1 == 1'b1) begin
state <= #1 GNT2;
gnt_1 <= req_0;
end
GNT2 : if (req_0 == 1'b1) begin
state <= #1 GNT1;
gnt_1 <= req_1;
end
default : state <= #1 IDLE;
endcase
end
endmodule
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