125 lines
3.9 KiB
Plaintext
125 lines
3.9 KiB
Plaintext
`ifndef SEVEN_SEG_H_SV
|
|
`define SEVEN_SEG_H_SV
|
|
|
|
module seven_seg(
|
|
input logic [3:0] num, // Input binary
|
|
input logic [0:0] rbi_inv, // Ripple blanking input
|
|
output logic [7:0] segments); // segent[0] = Ripple blanking out, segment[1] to segment[7] 7 seg LEDs
|
|
|
|
always_comb begin
|
|
case (num) // implement truth table as case statement
|
|
4'b0000: segments = (rbi_inv) ? ~(8'b01111111) : ~(8'b00000000); // zero or blank
|
|
4'b0001: segments = ~(8'b00001101);
|
|
4'b0010: segments = ~(8'b10110111);
|
|
4'b0011: segments = ~(8'b10011111);
|
|
4'b0100: segments = ~(8'b11001101);
|
|
4'b0101: segments = ~(8'b11011011);
|
|
4'b0110: segments = ~(8'b11111011);
|
|
4'b0111: segments = ~(8'b00001111);
|
|
4'b1000: segments = ~(8'b11111111);
|
|
4'b1001: segments = ~(8'b11001111);
|
|
4'b1010: segments = ~(8'b11101111);
|
|
4'b1011: segments = ~(8'b11111001);
|
|
4'b1100: segments = ~(8'b01110011);
|
|
4'b1101: segments = ~(8'b10111101);
|
|
4'b1110: segments = ~(8'b11110011);
|
|
4'b1111: segments = ~(8'b11100011);
|
|
default: segments = ~(8'bxxxxxxxx);
|
|
endcase
|
|
end
|
|
endmodule
|
|
|
|
module seven_seg_2digit(
|
|
input logic [3:0] b, // left
|
|
input logic [3:0] a, // right
|
|
output logic [7:0] seg_b, // left
|
|
output logic [7:0] seg_a); // right
|
|
|
|
// seg_b
|
|
seven_seg left_digit(
|
|
.num(b),
|
|
.rbi_inv(1'b0), // blanking enabled
|
|
.segments(seg_b)
|
|
);
|
|
|
|
// seg_a
|
|
seven_seg right_digit(
|
|
.num(a),
|
|
.rbi_inv(1'b1), // blanking disabled
|
|
.segments(seg_a)
|
|
);
|
|
|
|
endmodule
|
|
`endif
|
|
|
|
// Testbench below
|
|
|
|
module seven_seg_tb();
|
|
logic [3:0] in_num;
|
|
logic [0:0] in_rbi_inv;
|
|
logic [7:0] out_segments;
|
|
logic [7:0] true_segments[17];
|
|
|
|
seven_seg dut(in_num, in_rbi_inv, out_segments);
|
|
|
|
integer N;
|
|
integer i;
|
|
integer error_count;
|
|
initial begin
|
|
|
|
// Initialise truth table
|
|
true_segments[0 ] = ~(8'b01111111);
|
|
true_segments[1 ] = ~(8'b00001101);
|
|
true_segments[2 ] = ~(8'b10110111);
|
|
true_segments[3 ] = ~(8'b10011111);
|
|
true_segments[4 ] = ~(8'b11001101);
|
|
true_segments[5 ] = ~(8'b11011011);
|
|
true_segments[6 ] = ~(8'b11111011);
|
|
true_segments[7 ] = ~(8'b00001111);
|
|
true_segments[8 ] = ~(8'b11111111);
|
|
true_segments[9 ] = ~(8'b11001111);
|
|
true_segments[10] = ~(8'b11101111);
|
|
true_segments[11] = ~(8'b11111001);
|
|
true_segments[12] = ~(8'b01110011);
|
|
true_segments[13] = ~(8'b10111101);
|
|
true_segments[14] = ~(8'b11110011);
|
|
true_segments[15] = ~(8'b11100011);
|
|
true_segments[16] = ~(8'b00000000); // Special case for RBI
|
|
|
|
$display("Beginning seven-segment tests");
|
|
|
|
in_num = 4'd0;
|
|
in_rbi_inv = 1'b0;
|
|
error_count = 0;
|
|
#1;
|
|
if (out_segments !== true_segments[16]) begin
|
|
$display("\t\x1b[38;5;9mNumber 0b%b failed to decode to 0b%b, producing 0b%b\x1b[m", in_num, true_segments[16], out_segments);
|
|
error_count = error_count + 1;
|
|
end
|
|
for (N=1; N < 15; ++N) begin
|
|
in_num = in_num + 1;
|
|
#1;
|
|
if (out_segments !== true_segments[N]) begin
|
|
$display("\t\x1b[38;5;9mNumber 0b%b failed to decode to 0b%b, producing 0b%b\x1b[m", in_num, true_segments[N], out_segments);
|
|
error_count = error_count + 1;
|
|
end
|
|
end
|
|
|
|
in_num = 4'd0;
|
|
in_rbi_inv = 1'b1;
|
|
for (N=0; N < 15; ++N) begin
|
|
#1;
|
|
if (out_segments !== true_segments[N]) begin
|
|
$display("\t\x1b[38;5;9mNumber 0b%b failed to decode to 0b%b, producing 0b%b\x1b[m", in_num, true_segments[N], out_segments);
|
|
error_count = error_count + 1;
|
|
end
|
|
in_num = in_num + 1;
|
|
end
|
|
|
|
if (error_count == 0) $display("\x1b[38;5;10mAll seven-segment tests passing\x1b[m");
|
|
else $display("\x1b[38;5;9m%0d seven-segment test(s) failing\x1b[m", error_count);
|
|
end
|
|
endmodule
|
|
|
|
|