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Re: [Xylo-SDR] Staus update and HELP WANTED!



Phil Harman wrote:
Fellow Xylons,

Most will know by now that Bob and I had a very constructive last few weeks. Bob has added support for the Xylo/Wolfson A/D and D/A into PowerSDR at 48k/16 bit and intial test are very incouraging.

^^^ Bill?
We recently changed the sync sequence from once in evey 2 L/R samples to once at the start of 512 bytes. This reduces the sync overhead and allows us to add command and control signals (C&C) within the audio data.

Bill has tested the new sync format within PowerSDR and again all looks good. I have also tested a simple C&C in that pressing the button on the Xylo turns the red LED off. This simulates a PTT.

I've also added 48k/24bit and 96k/24bit A/D for the Wolfson and Bill is going to test this shorltly.

Next I'm going to breadboard the TLV320AIC23B as a mic/line in device A/D and headphone/line out D/A device.

This chip makes extensive use of I2C to initially set up various parameters and then adjust levels and gains etc. We need to be able to do this from the FPGA and therefor need an I2C Master developed in Verilog.

There is a potential source of such code at www.opencores.com but it will need porting and testing on the Xylo. The opencores documentation looks very good and the task not too onnerouse. We really could do with some help if were are to move this project on at a good rate of progress. So if someone would like to tackle the I2C master then it would be a nice little self contained project.

We also need a PCB designer to layout the Janus board. Whilst Bill and I will get round to it eventually I prefer breadboards and Bill's programing skills, in my veiw, are much more valuable working on code at the moment. This does not mean we will not eventually produce a PCB - it will just take significantly longer (and if left up to me much longer!).

Anyone interested in helping please step up!

73's  Phil...VK6APH

Great stuff.

Bob

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