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Thoughts on a cheap, hobbyist USBi?

Question asked by gmarsh on Feb 15, 2012
Latest reply on Apr 21, 2016 by CoryHenderson

I've designed an amplifier card for a solar powered camping stereo, which uses an ADAU1701 SigmaDSP for filtering, active crossover, bass/loudness enhancement and other features. I'm releasing the card as an open source project, to match the 'open source' nature of the original camping stereo design, and I'd like to encourage people to mess with the SigmaDSP code on the card and improve it as much as they can.


The stereo in question is called the "Boominator". It's small, it's loud, it sounds great, and it runs on solar power.


The design log for my SigmaDSP based card.


On the current card design, the SigmaDSP is booted by an Atmel AVR processor. Users can download SigmaStudio and make alterations to the SigmaDSP code, recompile the AVR software with new SigmaDSP code, and reprogram the AVR with an ISP programmer. But if people want to perform "live tweaking" of the design when they're listening to it, they need to use a USBi. Unfortunately the cost of a USBi ($250+) is prohibitive for basically any hobbyist.




If I took the basic USBi hardware design, replaced the BGA FX2LP with a SSOP part, changed to PCB to 2 layers and eliminated the SPI interface, I figure I could build a "cheap USBi" for about 25 dollars in low quantity. Only matter is the software to run on the FX2LP - theoretically I could cross my fingers and copy the USBi's EEPROM contents onto the newly created card and it might work, but I can't afford a lawyer


So, is there any hope of getting official ADI blessing, and software, for a cheap USBi gadget?




- The "cheap USBi" hardware design will be freely published and available, anyone can build them if they want (I hold no financial interest)

- ADI won't have to release any source code, protocol IP, etc - a binary EEPROM image is fine.

- ADI has zero responsibility for any issues with the "cheap USBi". Users understand that if they need a proper development tool for commercial development purposes, they should buy the real thing.


And why I believe Analog Devices should allow such a gadget:


- You'll make SigmaDSP parts more attractive to hobbyists. Free development tools and inexpensive, third party programming tools are why Atmel AVR basically dominates the hobby microcontroller market, I can't see why SigmaDSP can't start making similar inroads in the DIY audio community.

- Hobbyists with SigmaDSP experience can find themselves with day jobs implementing SigmaDSP parts in commercial designs.

- Very little work involved. If the stock USBi EEPROM image runs on the "cheap USBi", you won't actually have to do any work. If switching FX2LPs requires small changes and a recompile, it should be only a small amount of work.


Thanks for your consideration!