ipunished
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Hi,
I have instantiated a stopwatch module into this multiplexer module. The stopwatch is working as it is supposed to and is producing the expected output. This is also picked up by the instantiated registers, but if I want to use this data further down the module, it does not work.
For example, here is the simulation showing my problem:
So the the values picked up from the stopwatch module are working perfectly. These values are then transferred to the registers ``regd0, regd1, regd2, regd3`` which, instead of displaying the values are displaying ``0``?
Here is the code that produced the above simulation:
I have instantiated a stopwatch module into this multiplexer module. The stopwatch is working as it is supposed to and is producing the expected output. This is also picked up by the instantiated registers, but if I want to use this data further down the module, it does not work.
For example, here is the simulation showing my problem:
So the the values picked up from the stopwatch module are working perfectly. These values are then transferred to the registers ``regd0, regd1, regd2, regd3`` which, instead of displaying the values are displaying ``0``?
Here is the code that produced the above simulation:
Code:
module muxer(
input clock,
input reset,
input [1:0] select,
output a,
output b,
output c,
output d,
output e,
output f,
output g,
output dp,
output [3:0] an
);
reg go_hi, go_start;
wire[3:0] wire_d0, wire_d1, wire_d2, wire_d3; // timer registers that will hold the individual counts
wire[3:0] wire_hd0, wire_hd1, wire_hd2, wire_hd3; //regsiters to hold the "hi" values
reg [3:0] regd0, regd1, regd2, regd3; //registers for LED multiplexing
//instantiate the "hi" module
say_hi sayhi(.clock(clock), .reset(reset), .go(go_hi), .hi_d0(wire_hd0), .hi_d1(wire_hd1), .hi_d2(wire_hd2), .hi_d3(wire_hd3)) ;
//instantiate the stopwatch module
stopwatch timer(.clock(clock), .reset(reset), .start(go_start), .d0(wire_d0), .d1(wire_d1), .d2(wire_d2), .d3(wire_d3) );
always @ (select)
begin
case(select)
00: //hi
begin
go_start = 0; //make sure timer module is off
go_hi = 1'b1; //enable go signal to display "hi"
regd0 = wire_hd0; //transfer values to the multiplexing circuit
regd1 = wire_hd1;
regd2 = wire_hd2;
regd3 = wire_hd3;
end
01: //timer
begin
go_hi = 0; //make sure "hi" module is off
go_start = 1'b1; //enable start signal to start timer
regd0 = wire_d0;
regd1 = wire_d1;
regd2 = wire_d2;
regd3 = wire_d3;
end
10: //stop timer
begin
go_hi = 0;
go_start = 1'b0;
end
endcase
end
//The Circuit for 7 Segment Multiplexing -
localparam N = 8; //18 for implementation, 8 for simulation
reg [N-1:0]count;
always @ (posedge clock or posedge reset)
begin
if (reset)
count <= 0;
else
count <= count + 1;
end
reg [6:0]sseg;
reg [3:0]an_temp;
reg reg_dp;
always @ (*)
begin
case(count[N-1:N-2])
2'b00 :
begin
sseg = regd0;
an_temp = 4'b1110;
reg_dp = 1'b1;
end
2'b01:
begin
sseg = regd1;
an_temp = 4'b1101;
reg_dp = 1'b0;
end
2'b10:
begin
sseg = regd2;
an_temp = 4'b1011;
reg_dp = 1'b1;
end
2'b11:
begin
sseg = regd3;
an_temp = 4'b0111;
reg_dp = 1'b0;
end
endcase
end
assign an = an_temp;
reg [6:0] sseg_temp;
always @ (*)
begin
case(sseg)
4'd0 : sseg_temp = 7'b1000000; //display 0
4'd1 : sseg_temp = 7'b1111001; //display 1
4'd2 : sseg_temp = 7'b0100100;// display 2
4'd3 : sseg_temp = 7'b0110000;
4'd4 : sseg_temp = 7'b0011001;
4'd5 : sseg_temp = 7'b0010010;
4'd6 : sseg_temp = 7'b0000010;
4'd7 : sseg_temp = 7'b1111000;
4'd8 : sseg_temp = 7'b0000000;
4'd9 : sseg_temp = 7'b0010000;
4'd10 : sseg_temp = 7'b0001001; //to display H
4'd11 : sseg_temp = 7'b0000111; //to display I
default : sseg_temp = 7'b0111111; //dash
endcase
end
assign {g, f, e, d, c, b, a} = sseg_temp;
assign dp = reg_dp;
endmodule