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|
module halfband_tb( ) ;
// Parameters for instantiation
parameter clocks = 2 ; // Number of clocks per input
parameter decim = 0 ; // Sets the filter to decimate
parameter rate = 2 ; // Sets the decimation rate
reg clock ;
reg reset ;
reg enable ;
reg strobe_in ;
reg signed [17:0] data_in ;
wire strobe_out ;
wire signed [17:0] data_out ;
// Setup the clock
initial clock = 1'b0 ;
always #5 clock <= ~clock ;
// Come out of reset after a while
initial reset = 1'b1 ;
initial #100 reset = 1'b0 ;
// Enable the entire system
initial enable = 1'b1 ;
// Instantiate UUT
halfband_ideal
#(
.decim ( decim ),
.rate ( rate )
) uut(
.clock ( clock ),
.reset ( reset ),
.enable ( enable ),
.strobe_in ( strobe_in ),
.data_in ( data_in ),
.strobe_out ( strobe_out ),
.data_out ( data_out )
) ;
integer i, ri, ro, infile, outfile ;
// Setup file IO
initial begin
infile = $fopen("input.dat","r") ;
outfile = $fopen("output.dat","r") ;
$timeformat(-9, 2, " ns", 10) ;
end
reg endofsim ;
reg signed [17:0] compare ;
integer noe ;
initial noe = 0 ;
initial begin
// Initialize inputs
strobe_in <= 1'd0 ;
data_in <= 18'd0 ;
// Wait for reset to go away
@(negedge reset) #0 ;
// While we're still simulating ...
while( !endofsim ) begin
// Write the input from the file or 0 if EOF...
@( posedge clock ) begin
#1 ;
strobe_in <= 1'b1 ;
if( !$feof(infile) )
ri = $fscanf( infile, "%d", data_in ) ;
else
data_in <= 18'd0 ;
end
// Clocked in - set the strobe to 0 if the number of
// clocks per sample is greater than 1
if( clocks > 1 ) begin
@(posedge clock) begin
strobe_in <= 1'b0 ;
end
// Wait for the specified number of cycles
for( i = 0 ; i < (clocks-2) ; i = i + 1 ) begin
@(posedge clock) #1 ;
end
end
end
// Print out the number of errors that occured
if( noe )
$display( "FAILED: %d errors during simulation", noe ) ;
else
$display( "PASSED: Simulation successful" ) ;
$stop ;
end
// Output comparison of simulated values versus known good values
always @ (posedge clock) begin
if( reset )
endofsim <= 1'b0 ;
else begin
if( !$feof(outfile) ) begin
if( strobe_out ) begin
ro = $fscanf( outfile, "%d\n", compare ) ;
if( compare != data_out ) begin
$display( "%t: %d != %d", $realtime, data_out, compare ) ;
noe = noe + 1 ;
end
end
end else begin
// Signal end of simulation when no more outputs
endofsim <= 1'b1 ;
end
end
end
endmodule
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