URL
https://opencores.org/ocsvn/apbi2c/apbi2c/trunk
Subversion Repositories apbi2c
Compare Revisions
- This comparison shows the changes necessary to convert path
/apbi2c
- from Rev 12 to Rev 13
- ↔ Reverse comparison
Rev 12 → Rev 13
/trunk/rtl/fifo.v
91,61 → 91,64
|
reg [AWIDTH-1:0] wr_ptr; |
reg [AWIDTH-1:0] rd_ptr; |
reg [AWIDTH-1:0] last_position; |
|
reg last_was_write; |
|
always @ (posedge clock) |
always@(posedge clock) |
begin |
|
if (reset) |
//SYNCHRONOUS RESET |
begin |
rd_ptr <= {AWIDTH{1'b0}}; |
wr_ptr <= {AWIDTH{1'b0}}; |
last_position <= {AWIDTH{1'b0}}; |
last_was_write <= 1'b1; |
|
// NONBLOCKING |
end |
else |
begin |
if (wr_en )//WRITE OPERATION |
begin |
mem[wr_ptr] <= data_in; //WRITE TO ARRAY |
wr_ptr <= wr_ptr + 11'd1; |
|
if(wr_ptr == {AWIDTH{1'b1}}) |
if(wr_en)//WRITE OPERATION |
begin |
mem[wr_ptr] <= data_in; //WRITE TO ARRAY |
wr_ptr <= wr_ptr + 11'd1; |
last_position <= last_position + 11'd1; |
|
last_was_write <= 1'b0; |
end |
|
rd_ptr <= {AWIDTH{1'b0}};//POINTER GOES TO INITIAL ADDRESSS |
|
end |
else if (rd_en)// READ OPERATION |
begin |
|
rd_ptr <= rd_ptr + 11'd1; |
rd_ptr <= {AWIDTH{1'b0}}; |
|
if(rd_ptr == {AWIDTH{1'b1}})//SIGNAL USED TO NOTICE I2C FIFO IS EMPTY |
begin |
last_was_write <= 1'b1; |
wr_ptr <= {AWIDTH{1'b0}};//POINTER GOES TO INITIAL ADDRESSS |
end |
else if(wr_ptr != {AWIDTH{1'b0}} && wr_ptr == rd_ptr )//HALF FULL EMPTY CONDITION |
else if(rd_en)// READ OPERATION |
begin |
last_was_write <= 1'b1; |
wr_ptr <= {AWIDTH{1'b0}};//POINTER GOES TO INITIAL ADDRESSS |
end |
|
wr_ptr <= {AWIDTH{1'b0}}; |
|
if(rd_ptr != {AWIDTH{1'b1}} && last_position == {AWIDTH{1'b0}}) |
begin |
rd_ptr <= rd_ptr + 11'd1; |
end |
else if(rd_ptr != last_position) |
begin |
rd_ptr <= rd_ptr + 11'd1; |
end |
|
if(rd_ptr == last_position - 11'b1 || rd_ptr == {AWIDTH{1'b1}}) |
begin |
last_was_write <= 1'b1; |
last_position <= {AWIDTH{1'b0}}; |
end |
|
end |
else if(wr_ptr != rd_ptr && !wr_en)//THIS INST TESTED YET |
begin |
last_was_write <= 1'b0; |
end |
end |
|
end |
|
end |
|
assign f_full = (!last_was_write)? 1'b1:1'b0; |
|
assign f_full = (!last_was_write | last_position != {AWIDTH{1'b0}} )? 1'b1:1'b0; |
assign f_empty = (last_was_write)? 1'b1:1'b0; |
assign data_out = mem[rd_ptr];//WRITE ON OUTPUT |
|