blob: 9a8e37ce98584eed76fcc19364a53b274cfdb01e (
plain)
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
|
module fifo_to_gpmc_async
(input clk, input reset, input clear,
input [17:0] data_i, input src_rdy_i, output dst_rdy_o,
output [15:0] EM_D, input EM_NCS, input EM_NOE,
input [15:0] frame_len);
// Synchronize the async control signals
reg [2:0] cs_del, oe_del;
reg [15:0] counter;
always @(posedge clk)
if(reset)
begin
cs_del <= 3'b11;
oe_del <= 3'b11;
end
else
begin
cs_del <= { cs_del[1:0], EM_NCS };
oe_del <= { oe_del[1:0], EM_NOE };
end
wire do_read = ( (~cs_del[1] | ~cs_del[2]) & (oe_del[1:0] == 2'b01)); // change output on trailing edge
wire first_read = (counter == 0);
wire last_read = ((counter+1) == frame_len);
assign EM_D = data_i[15:0];
assign dst_rdy_o = do_read;
endmodule // fifo_to_gpmc_async
|
