test(pingxelflut): add testbench

Makefile

@@ -14,7 +14,7 @@ clean:
 prog: pixelflut.bit
 	openFPGALoader -b arty_a7_35t $<
 
-sim: dvi_tb.vcd
+sim: dvi_tb.vcd pingxelflut_tb.vcd
 
 pixelflut.bit: pixelflut.frames
 	xc7frames2bit --part_file "$(XRAY_DATABASE_DIR)/artix7/$(PART)/part.yaml" --part_name $(PART) --frm_file $< --output_file $@
@@ -33,3 +33,9 @@ dvi_tb.vcd: dvi_tb.vvp
 
 dvi_tb.vvp: dvi_tb.v dvi.v
 	iverilog -o $@ $^
+
+pingxelflut_tb.vcd: pingxelflut_tb.vvp
+	vvp $<
+
+pingxelflut_tb.vvp: pingxelflut_tb.v pingxelflut.v
+	iverilog -o $@ $^

pingxelflut.v

@@ -1,7 +1,7 @@
 module pingxelflut #(
 	parameter MAC_ADDRESS = 48'h02_00_00_00_00_00,
 
-	parameter SCREEN_WIDTH = 346,
+	parameter SCREEN_WIDTH = 346
 ) (
 	input             rx_clk,
 	input       [3:0] rxd,
@@ -11,7 +11,7 @@ module pingxelflut #(
 	output reg        bus_clk,
 	output reg [15:0] bus_data,
 	output reg [23:0] bus_addr,
-	output reg  [1:0] bus_sel,
+	output reg  [1:0] bus_sel
 );
 	localparam PREAMBLE          = 7'b0000000;
 	localparam DEST_0            = 7'b0000001;

pingxelflut_state.txt

@@ -0,0 +1,64 @@
+0000000 PREAMBLE
+0000001 DEST_0
+0000010 DEST_1
+0000011 DEST_2
+0000100 DEST_3
+0000101 DEST_4
+0000110 DEST_5
+0000111 DEST_6
+0001000 DEST_7
+0001001 DEST_8
+0001010 DEST_9
+0001011 DEST_A
+0001100 DEST_B
+0001101 SRC_0
+0001110 SRC_1
+0001111 SRC_2
+0010000 SRC_3
+0010001 SRC_4
+0010010 SRC_5
+0010011 SRC_6
+0010100 SRC_7
+0010101 SRC_8
+0010110 SRC_9
+0010111 SRC_A
+0011000 SRC_B
+0011001 ETHER_TYPE_0
+0011010 ETHER_TYPE_1
+0011011 ETHER_TYPE_2
+0011100 ETHER_TYPE_3
+0100000 TRAFFIC_CLASS_0
+0100001 VERSION
+0100010 FLOW_LABEL_0
+0100011 TRAFFIC_CLASS_1
+0100100 FLOW_LABEL_1
+0100101 FLOW_LABEL_2
+0100110 FLOW_LABEL_3
+0100111 FLOW_LABEL_4
+0101000 PAYLOAD_LENGTH_0
+0101001 PAYLOAD_LENGTH_1
+0101010 PAYLOAD_LENGTH_2
+0101011 PAYLOAD_LENGTH_3
+0101100 NEXT_HEADER_0
+0101101 NEXT_HEADER_1
+0101110 HOP_LIMIT_0
+0101111 HOP_LIMIT_1
+0110000 SRC_ADDR_0
+1010000 DEST_PREFIX_0
+1100000 X_0
+1100001 X_1
+1100010 X_2
+1100011 X_3
+1100100 Y_0
+1100101 Y_1
+1100110 Y_2
+1100111 Y_3
+1101000 RED_LOW
+1101001 RED_HIGH
+1101010 GREEN_LOW
+1101011 GREEN_HIGH
+1101100 BLUE_LOW
+1101101 BLUE_HIGH
+1101110 PADDING_LOW
+1101111 PADDING_HIGH
+1111111 IGNORE

pingxelflut_tb.hex

@@ -0,0 +1,129 @@
+d
+2
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pingxelflut_tb.v

@@ -0,0 +1,42 @@
+`timescale 1 ns / 1 ns
+
+module testbench();
+	reg clk = 0;
+
+	always #20 clk = ~clk;
+
+	reg [3:0] rxd;
+
+	wire        bus_clk;
+	wire [15:0] bus_data;
+	wire [23:0] bus_addr;
+	wire  [1:0] bus_sel;
+
+	pingxelflut eth (
+		.rx_clk  (clk),
+		.rxd     (rxd),
+		.rx_dv   (1'b1),
+		.rx_er   (1'b0),
+
+		.bus_clk (bus_clk),
+		.bus_data(bus_data),
+		.bus_addr(bus_addr),
+		.bus_sel (bus_sel)
+	);
+
+	reg [3:0] test_data [0:128];
+
+	initial begin
+		$dumpfile("pingxelflut_tb.vcd");
+		$dumpvars(0, testbench);
+
+		$readmemh("pingxelflut_tb.hex", test_data);
+
+		rxd <= test_data[0];
+		#10;
+		for (integer i = 1; i < 129; i = i + 1) #40 rxd <= test_data[i];
+
+		$finish;
+	end
+endmodule
+