1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
|
// Model of FIFO in Altera
module fifo( data, wrreq, rdreq, rdclk, wrclk, aclr, q,
rdfull, rdempty, rdusedw, wrfull, wrempty, wrusedw);
parameter width = 16;
parameter depth = 1024;
parameter addr_bits = 10;
//`define rd_req 0; // Set this to 0 for rd_ack, 1 for rd_req
input [width-1:0] data;
input wrreq;
input rdreq;
input rdclk;
input wrclk;
input aclr;
output [width-1:0] q;
output rdfull;
output rdempty;
output reg [addr_bits-1:0] rdusedw;
output wrfull;
output wrempty;
output reg [addr_bits-1:0] wrusedw;
reg [width-1:0] mem [0:depth-1];
reg [addr_bits-1:0] rdptr;
reg [addr_bits-1:0] wrptr;
`ifdef rd_req
reg [width-1:0] q;
`else
wire [width-1:0] q;
`endif
integer i;
always @( aclr)
begin
wrptr <= #1 0;
rdptr <= #1 0;
for(i=0;i<depth;i=i+1)
mem[i] <= #1 0;
end
always @(posedge wrclk)
if(wrreq)
begin
wrptr <= #1 wrptr+1;
mem[wrptr] <= #1 data;
end
always @(posedge rdclk)
if(rdreq)
begin
rdptr <= #1 rdptr+1;
`ifdef rd_req
q <= #1 mem[rdptr];
`endif
end
`ifdef rd_req
`else
assign q = mem[rdptr];
`endif
// Fix these
always @(posedge wrclk)
wrusedw <= #1 wrptr - rdptr;
always @(posedge rdclk)
rdusedw <= #1 wrptr - rdptr;
assign wrempty = (wrusedw == 0);
assign wrfull = (wrusedw == depth-1);
assign rdempty = (rdusedw == 0);
assign rdfull = (rdusedw == depth-1);
endmodule // fifo
|
