Open Hardware DSP Platform

Thanks,
I also watched a YouTube with SigmaStudio .
I have a question on the usb eval board. I will use a CY7C68013A--Cypress board with the freeusbi board on top. Now the freeusb uses a 5v supply on pin 4 of the interface to their dsp. I can set it up to have no voltage on pin 4. But looking at the schematic for header 506 I see no voltage reference on pin 4. I do see the reference to 3v3 lines. Will the dsp get the power needed from the clk , etc pins? If needed i will purchase the AD usb board but i am just trying to save the 130 cad for the programmer.
Thanks,
Carlos
 
i was hoping to get away with conventional soldering:eek:, so far i was fine with 0805, have not touched anything smaller :) so there is lots to learn.
@carlos. i guess for now i would like to nail together one DSP, and a reflow oven would be awesome but it is sort of blowing things out of proportion for me..

maybe a hot air station would do the job for..
Paul, did you solder the dsp from your project page with a normal soldering iron?
the XMOS is for the "control board"? i was wondering how this is getting along:)
J
 
I did three DSP chips with a normal soldering iron (2.4mm bit? or bigger...). The big via in the thermal pad makes it easier to do. Using solder wick around the edge pads seems to help apply solder in just the right amount and remove any excess at the same time, but you need some extra flux.

The xmos chips didn't work so well. The first one soldered to the PCB okay but there was a permanent short between two of the power rails, after much head scratching the only solution was to remove the XMOS chip itself. The PCB seemed okay, but when trying to fit the replacement XMOS chip the large via in the thermal pad just started to disintegrate writing off the whole PCB.

As the XMOS chips (XEF216-512-TQ128) I was using cost £15 each, and I had identified several design issues already, I am working on a revised PCB. It should be easier to build. Also a lower memory version of the XMOS chip (XEF216-256-TQ128) is now available which is half the cost.

I am working on other PCB redesigns as well, and a new AK4458 DAC pcb. Supply of the ADAU1966 seems to have dried up a bit, or costs a lot more than I last paid. Once I have these I will order a few new batches of blank boards to build up when I have time.
 
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Hi ohdsp.
Thank you for sharing this project. Great flexible boards to use as per requirement.

I have a question. What is the role/functions of Xmos board? I see the multiple interfaces USB, Ethernet, SPDIF, I2S, I2C etc.
I was wondering if it is also used as an MCU for 1452DSP chip for real time parameter settings control like using buttons or rotary encoder with display?

Thank you.
 
Thanks princenk007,

I based my original idea around the ADAU1452 as it is just simple to use, and ideal for systems using as crossovers/equalisers, maybe even some simple room correction. As a stand alone board it is very flexible.

My long term goal is to play with USB audio and network streaming/control if I can. I also wanted a microcontroller so you could add in an array of external controls/display and so on. The XMOS 200 chip looked like it might fulfil most of the roles, and possibly even some DSP functions as well removing the need for the ADAU1452 board in some instances - such as a USB sound card.

It's all a long way off, the new design revisions I am working on are mostly there, but I need to finish and check these. There are also several bugs I need to work out on the old hardware before I finish these. There would be the coding needed for the XMOS 200 and this may take a while.

Cheers.
 
No built PCBs available. You can order blank PCBs from places like JLCPCB or DirtyPCB with the Gerbers and build yourself if you felt inclined.

I have new designs I would release. Few issues with KiCad 5 libraries that I can't get working on multiple machines, and have caused some other headaches. Would prefer everything to work as expected.
 
release

No built PCBs available. You can order blank PCBs from places like JLCPCB or DirtyPCB with the Gerbers and build yourself if you felt inclined.

I have new designs I would release. Few issues with KiCad 5 libraries that I can't get working on multiple machines, and have caused some other headaches. Would prefer everything to work as expected.

Please tell me, when and where it will be released?
 
There is no release date, and no plan for selling assembled boards at this time. Just a collection of designs other people can use if they want. Generally I release new design files when I send things to get blank PCBs made.

Had been hoping to do some more this month. But with my slight KiCad 5 issues this will have to wait until after Christmas when I have some time to dig into this.
 
Hi again!
Okay, hope that new pcb coming soon...

I have few questions, can you give me anwser it?

1) Does it make sense to wait for a new release of the project's boards, or i can order production PCB based on old gerbers for complete and use it?

2) In general, there are some critical errors on the old board, and how much will the new board differ from the old one?
 
Thanks for the questions.

Current designs do work, although waiting for newer revisions might be the better option. I have had issues getting hold of the ADAU1966 DAC chips for a while, RS now have them in stock but at 3 times the price I last paid! :mad: I have a new AK4458 design I would really like to try, but that is a new design.

In terms of major issues; nothing that has stopped me working with these boards so far. Anything that was an issue I have designed out in the revisions currently on GitHub. I have two ADAU1966 DAC boards that have 1.7V reference voltages instead of the 2.5V specified in the datasheet. I only found this by chance as it had not been impacting what I was doing, but still need to get to the bottom of it. :wrench:

I have just setup my electronics gear again, having moved a few months back. However it looks like I might be moving again soon and real life keeps getting in the way of working on this, as does a lack of free money. :(

Changes on the new designs, well I have simplified the XMOS 200 design I have. The last one was a bit cramped to hand solder and I still don't have anything more exotic than an old fashioned soldering iron.

Other changes are mostly to do with voltage regulators and reset circuits. For example on the ADAU1452 DSP board I have found a nice buck converter designed to drive this type of IC directly. I have simplified the PSU by removing the 1.2V linear regulator, but this is not yet tested.

I have tried to simplify the reset circuits as well, and use cheaper parts. Anything else I have forgotten, I will try and work through the change logs before releasing designs though.

A nice Christmas break should help speed some of this work up a bit though, and give me a chance to order some presents for myself. :santa2: :D
 
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Did get some work done on this over the new year. Had hoped to order boards, but ended up reworking a layout.

Been trying to decide if I should use 2 or 4 layer boards on some designs. 4 layer boards are not that expensive, but 2 are much cheaper. With the AK4458 design I had been trying to fit it on 2 layers, but not happy with the breaks in the ground plane unless I added wire links. I had moved to 4 layers again for this, which is much easier to get a good layout with.