The fifo will ask for a new data from the DDR, if the current
level is lower than the high threshold. This will prevent overflow.
By deleting the lower threshold, we can avoid ocassional underflows,
when the DAC rate is closer to the max DDRx rate.
Fix the dma_ready mux in top module, and the dma_ready_out reset
logic in axi_dacfifo_wr module. Also, both write and read addresses
of the async CDC fifo (inside the axi_dacfifo_wr) should be reset
before a dma transaction starts.
All the hdl (verilog and vhdl) source files were updated. If a file did not
have any license, it was added into it. Files, which were generated by
a tool (like Matlab) or were took over from other source (like opencores.org),
were unchanged.
New license looks as follows:
Copyright 2014 - 2017 (c) Analog Devices, Inc. All rights reserved.
Each core or library found in this collection may have its own licensing terms.
The user should keep this in in mind while exploring these cores.
Redistribution and use in source and binary forms,
with or without modification of this file, are permitted under the terms of either
(at the option of the user):
1. The GNU General Public License version 2 as published by the
Free Software Foundation, which can be found in the top level directory, or at:
https://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html
OR
2. An ADI specific BSD license as noted in the top level directory, or on-line at:
https://github.com/analogdevicesinc/hdl/blob/dev/LICENSE
Xilinx recommends that all synchronizer flip-flops have
their ASYNC_REG property set to true in order to preserve the
synchronizer cells through any logic optimization during synthesis
and implementation.
Istvan Csomortani
Rejeesh Kutty
Adrian Costina