DSP Design with Analog Devices SigmaStudio

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Hi everyone,

I found some interesting videos online today for Analog Devices SigmaStudio, which is a graphical design program for DSP applications using Analog Devices SigmaDSP and SHARC processors.

Overview: http://www.youtube.com/watch?v=PPmkCVz5LAs

More features: http://www.youtube.com/watch?v=ihBhGDcYYKs

The most exciting feature is the ability to predict system performance within the program before writing to the DSP module, based on transformations of measured response data, but the LabView-style drag-and-drop modules and the ability to 'draw' signal routing are also very attractive. And best of all, it's a free download, which is a genius marketing move.

Has anyone here on Tech Talk done DSP development in the past with SigmaStudio? If so, what were your impressions?

Thanks in advance.

[Ron_E]

Re: DSP Design with Analog Devices SigmaStudio

Very cool software. The eval boards aren't cheap. http://www.analog.com/en/content/sig...oards/fca.html

Ron

[charlielaub]

Re: DSP Design with Analog Devices SigmaStudio

Rory, you should contact Neil Davis. I believe that he has worked with Sigma Studio extensively as well as related DSP hardware. He also has been developing his own DSP boards with onboard microcontrollers, which someday we hope to see finished...

-Charlie

[neildavis]

Re: DSP Design with Analog Devices SigmaStudio

Rory, you should contact Neil Davis. I believe that he has worked with Sigma Studio extensively as well as related DSP hardware. He also has been developing his own DSP boards with onboard microcontrollers

SigmaStudio is a nice tool, but it is actually a specialized program just for specifying the DSP architecture. Chips like the ADAU1701 (the one used in miniDSP) can execute 1024 program instructions every audio sample point, and SigmaStudio is how you define those program instructions. The instructions are building blocks for filters, volume controls, delay, and other DSP functions. SigmaStudio lets you define your DSP program graphically, so you can just drag filters, delays, selectors, etc., onto the SigmaStudio workspace and specify their connections and parameters. It will then compile a program for you that you can download into a variety of Analog Devices chips.

But once you have a running program, you still need to interact with the DSP chip in real time, and SigmaStudio doesn't do that. For example, if you want to change the filter parameters, or change the volume, or select another input, you need to develop your own GUI and provide a micro to update the Parameter RAM inside the DSP chip that is associated with that filter or volume control. So SigmaStudio is just a starting point for a much longer chain of software that is required to do interesting things with the DSP. If you only need to run a fixed program with no real time interaction, SigmaStudio is adequate. But for most applications you will also need code for a microprocessor to control the DSP plus an additional GUI on your host to send data to the micro.

I've been using the reference circuit for the ADAU1701, but I'm starting to work with other devices in the SigmaDSP family and using my own variations. For example, see the board in the picture below, which is the receiver board for the wireless SPDIF design that Charlie and I have been discussing. The ADAU1701 is in the upper left, and it receives I2S audio from the 5.8GHz "SPDIF datalink". The micro is the small chip at the bottom of the board near the USB connector. The GUI runs on a PC, but on this board there is a Bluetooth module that will allow receiving commands from a tablet.

which someday we hope to see finished... -Charlie

Ouch :rolleyes:

Well, I don't have any mass-produced boards, that's true, and the board in the picture is just starting to get debugged. But in that board with the ADAU1701 and SSM3302 chips, I can change the inputs, change the ADAU1701 volume and design crossovers by changing the filter parameters for the biquads. In other words, it is a real working prototype with code for the DSP that is well into Beta stage. So I can honestly say that it is a finished prototype :p

[SirNickity]

Re: DSP Design with Analog Devices SigmaStudio

You're a brilliant guy Neil. I wish I had half your skill. But your PCB traces make my OCD flare up like vinegar on baking soda. :D heheh

[neildavis]

Re: DSP Design with Analog Devices SigmaStudio

...But your PCB traces make my OCD flare up like vinegar on baking soda. :D heheh

You are not the first person to comment on my non-rectilinear traces:o . However, I've been making boards for a long time now, and old habits don't die easily. Check out this article from 1981:

[SirNickity]

Re: DSP Design with Analog Devices SigmaStudio

Haha, yeah.. I get it. The electrons don't care. And I did notice similarities to boards designed in the 80s.

I spend ridiculous amounts of time pouring over layout in the software, moving components around so they meet performance requirements and look neat... not to mention admiring a completed board like a teenage girl in front of a mirror. lol I don't know if I could ever do this professionally. "Is that board design done yet??" "Uh, no..." "What's holding it up?" "It looks lopsided..." :-\

[neildavis]

Re: DSP Design with Analog Devices SigmaStudio

SigmaStudio is a nice tool, but it is actually a specialized program just for specifying the DSP architecture...

After thinking about this, I need to revise it.

At least some of the Analog Devices DSP devices have separate A/D converters for reading controls. If you use this feature, you would be able to change volume and filter settings using volume controls connected to the chip, without having to use a separate micro and a GUI. For example, the ADAU1701 has a 4-channel 8-bit ADC. SigmaStudio lets you map the value read from the ADC channels to some of the controls. So you could configure the ADAU1701 to have a volume control cell that would be adjustable from a potentiometer that is connected to one of the multipurpose pins. Similarly, you could use a potentiometer to control the adjustments for a spatializer cell for a television sound bar, or you could control the amount of delay for a driver. Obviously, there are limits to what you can do with potentiometers and 8-bit ADC's, but it is a nice feature that allows you to use the DSP/SigmaStudio without any additional software.

[SirNickity]

Re: DSP Design with Analog Devices SigmaStudio

Interesting point.

To me, it doesn't make much sense to try and eliminate the micro from a digital audio device. The extent of my experience is limited here, but at least with Atmel AVRs, the development environments are so easy and inexpensive (free software, and maybe $30 for a cable or programmer to get you started) that there's certainly no technical barrier to entry. That is, if you're sharp enough to be talking about rolling your own DSP and DACs, you probably aren't bothered by at least one of the available low-end micros out there.

Having gone through a few DAC datasheets, they seem to assume there's an intelligent device available to set up the hardware. Many of them do have a hardware-only mode, but it usually comes with some caveats. Only i2s input, or fixed filtering, etc. Maybe OK for a single-purpose device (e.g., CD player) but anything that has an SPDIF input jack will probably require a little more than pull-ups and an analog knob or two. ;)

I guess my point here is, trying to build a device with DSP and no microcontroller seems counter-productive. What practical device that warrants DSP wouldn't be better served or already require a micro anyway?

[neildavis]

Re: DSP Design with Analog Devices SigmaStudio

Interesting point.

To me, it doesn't make much sense to try and eliminate the micro from a digital audio device.

It depends on the application. The ADI chips have a self-boot mode that allows the chip to load itself from an EEPROM, and the SigmaStudio tools can initialize the EEPROM. I can see where this stand-alone capability might be important in a cost-sensitive mass-produced product. And for some experimenters who can't or don't want to program micros, this capability might be of interest.

I brought this up because ADI went through the trouble of designing in this stand-alone self-boot capability and providing the ability to read potentiometers, and I didn't want to short-change their design. But for projects I am interested in, I need a GUI and the only way to provide a high-level user interface is to use an embedded controller that sits between the host/GUI and the DSP. So for the most part, I agree with you...but I wanted to be fair :rolleyes:

[Insomnia]

Re: DSP Design with Analog Devices SigmaStudio

I want to know....

How about Arduino MCU Boards to use with ADAU 1701 ?
with Arduino MCU boards can add easy LCD, Bluetooth, Wifi ....

what I want is to control simpe DIY Class D Amplifier Board
with Adau 1701 DSP, MCU LCD Display + Keypad look picture

but cant find solution, Analog no have referene design for this simple application and its hard to find people to help and understand what to do

[charlielaub]

Re: DSP Design with Analog Devices SigmaStudio

I want to know....

How about Arduino MCU Boards to use with ADAU 1701 ?
with Arduino MCU boards can add easy LCD, Bluetooth, Wifi ....

what I want is to control simpe DIY Class D Amplifier Board
with Adau 1701 DSP, MCU LCD Display + Keypad look picture

but cant find solution, Analog no have referene design for this simple application and its hard to find people to help and understand what to do

You are correct - AD does not make it easy for the end user to directly program their ADAU series boards without sigma studio. I think of you are dreaming of building a plate amp with a display from which you can control DSP parameters you should forget about it. Neil has been working on code to do this kind of thing for a couple of years now and he is still saying that it is not quite there yet. I think that by the time that he finishes the project it will be GREAT, but the ADAU product series will be discontinued!

-Charlie

[Insomnia]

Re: DSP Design with Analog Devices SigmaStudio

Yes I dreaming of building a plate amp with a display from which you can control DSP parameters

1. look here there is a guy offer Digital equalizer module ADAU1701 (2 * 31 * 6-band parametric paragraph 2 EQ) development board

http://www.dinobuy.com/p/p6773519-digital-equalizer-module-adau1701-2-31-6-band-parametric-paragraph-2-eq-development-board.html#ProductDescription

I think to make finished working project for plate amp is a dream too with this development board

I have this development board from a friend with x/over software look picture


2. How about CS47024 DSP from Cirrus ? look PDF file

I see there is embedded development board to buy with LCD and keypad but not cheap, Cirrus have a GUI programming development platform

The CS470xx Family is programmed using Cirrus Logic’s proprietary GUI software development tool called
DSP Composer.™ An audio processing chain is designed
using a drag and drop interface. The tool then configures
the CS470xx device through the SPI™/I2C® serial port.
The firmware may be loaded from the ROM within the
CS470xx device or it may be downloaded through the
serial control port.

[neildavis]

Re: DSP Design with Analog Devices SigmaStudio

Neil has been working on code to do this kind of thing for a couple of years now and he is still saying that it is not quite there yet.

That's really not the case. The code I've got that is specific to the ADAU1701 works and has all the required functionality. Right now I can develop a DSP architecture with SigmaStudio, generate the Parameter RAM map for the variables in the .NET GUI, generate the header file for the assembler, output commands to change volume and biquads and other resources from the PC GUI via USB, and then control the ADAU1701 with the micro. It even uses the safe-load registers so you can change the ADAU1701 parameters in real time.

I've had all of that functionality working for a long time--controlling the ADAU1701 is not the issue. And I can do the same thing for the STA308a DSP, or an STA328 or even a now-obsolete TAS3004 chip.

My interest in all of this has been for active speakers, and I've got a software architecture that integrates box design, baffle design, allows processing measurement files, and that allows me to design crossovers and EQ for active speakers with a wide variety of DSP's and amps with embedded DSP. It's all that other stuff that ends up slowing me down. Once I got the ADAU1701 code working reasonably well, I went back and finished off the modules that are in PSD-Lite. That's because the active speaker design program (ASD) uses the same modules, and I wanted them DONE. But once I got PSD-Lite in decent shape, I had to go back and rework some of the ASD code, but I haven't finished that yet. So that's why I never got around to sending you a piggy-back board to play with--I still need to put a bit more time into ASD before sending you a copy. I'll see if I can get a rough version tested and I'll send it off to you soon.


edit--what I'll send you is one of those piggy-back boards and a link to download ASD. The piggy-back board plugs into the miniDSP and lets you program the ADAU1701 from the micro. I had looked at your spreadsheet to see how easy it would be to add the code to communicate with the piggy-back board using the FTDI USB driver, but just didn't have the initiative to follow-through. If you've got some ideas on how you want to do it (what buttons to add...) send me an email.