Files
Ethernet-IP-Core/hdl/fifo_to_tpsram_bridge.v

79 lines
2.2 KiB
Verilog

module fifo_to_tpsram_bridge #(
parameter DATA_WIDTH = 32,
parameter ADDR_WIDTH = 10 // 1024 depth
)(
input wire clk,
input wire reset_n,
// CoreFIFO Interface (FWFT Mode)
input wire [DATA_WIDTH-1:0] fifo_data_out,
input wire fifo_empty,
output reg fifo_rd_en,
// TPSRAM Port A Interface (Write Port)
output reg [ADDR_WIDTH-1:0] ram_w_addr,
output reg [DATA_WIDTH-1:0] ram_w_data,
output reg ram_w_en,
// Control/Status
input wire transfer_enable,
output reg buffer_full
);
// State Encoding
localparam IDLE = 2'b00,
WRITE = 2'b01,
FULL = 2'b10;
reg [1:0] state, next_state;
// Address Counter Logic
always @(posedge clk or negedge reset_n) begin
if (!reset_n) begin
ram_w_addr <= 0;
buffer_full <= 0;
end else if (ram_w_en) begin
if (ram_w_addr == {ADDR_WIDTH{1'b1}}) begin
buffer_full <= 1; // Memory is topped off
end else begin
ram_w_addr <= ram_w_addr + 1;
end
end
end
// FSM State Transitions
always @(posedge clk or negedge reset_n) begin
if (!reset_n) state <= IDLE;
else state <= next_state;
end
// Next State Logic
always @(*) begin
next_state = state;
case (state)
IDLE: begin
// Start writing if FIFO has data and RAM isn't full
if (!fifo_empty && transfer_enable && !buffer_full)
next_state = WRITE;
end
WRITE: begin
if (fifo_empty || buffer_full)
next_state = IDLE;
end
default: next_state = IDLE;
endcase
end
// Output Logic
always @(*) begin
fifo_rd_en = 0;
ram_w_en = 0;
ram_w_data = fifo_data_out;
if (state == WRITE && !fifo_empty && !buffer_full) begin
fifo_rd_en = 1;
ram_w_en = 1;
end
end
endmodule