khutch
It confused me too! Both sides are at 3.3v. I believe that the function is to allow the interface to be disabled, ie it allows the PC to take control of the I2C interface or leave it to the ADAU to be master, under control of the signal USB_PWR_ON ...(low grounds the gate, blocking transconductance).. does that make sense to you?? Regardless, as per my earlier posts, it works
It confused me too! Both sides are at 3.3v. I believe that the function is to allow the interface to be disabled, ie it allows the PC to take control of the I2C interface or leave it to the ADAU to be master, under control of the signal USB_PWR_ON ...(low grounds the gate, blocking transconductance).. does that make sense to you?? Regardless, as per my earlier posts, it works
Last edited:
Yes, I think you are right. Shortly after I posted the question I was thinking about an application note that described the circuit. It had a two transistor version where either the high or low voltage side could be powered down without disturbing the devices on the other side. It suddenly struck me that the most likely purpose of the "level shifters" on those two lines was to allow the ADAU1701 and its EEPROM to communicate in self boot mode when the USB device was powered down. In this case you need only one transistor instead of two because the situation where the USB side is powered and the DSP side is not can't support I2C communications anyway. The level shifters are nice to have but not strictly needed, it appears, if you don't need to keep the USB interface physically connected to the DSP when the latter is in self boot mode.
For those who are interested in building the FreeDSP USBi board:
I have 20 USBi PCBs that I ordered from Elecrow. I'll mail you one if you send me $2.00 via Paypal (ernperkins at msn dot com) and provide a mailing address. This assumes you're in the USA. I'm not making any money on these so I think it's OK to use the Friends/Family option in PayPal.
I also created a public cart at Digikey for the USBi parts. The cart is a duplicate of the FreeDSP BOM except the USBi ribbon cable is 5 ft. vs. 3 meters.
For the Sure ADAU1701 DSP:
- Only one cable connector (part ED10500-ND) is needed; the cart has two specified.
- If you're connecting to the Sure 6-pin header you can also order cable #455-3140-ND. It's a 6 inch cable with a 6-pin socket on each end. Cut it in half and you have two 6-pin sockets.
Enjoy!
I have 20 USBi PCBs that I ordered from Elecrow. I'll mail you one if you send me $2.00 via Paypal (ernperkins at msn dot com) and provide a mailing address. This assumes you're in the USA. I'm not making any money on these so I think it's OK to use the Friends/Family option in PayPal.
I also created a public cart at Digikey for the USBi parts. The cart is a duplicate of the FreeDSP BOM except the USBi ribbon cable is 5 ft. vs. 3 meters.
For the Sure ADAU1701 DSP:
- Only one cable connector (part ED10500-ND) is needed; the cart has two specified.
- If you're connecting to the Sure 6-pin header you can also order cable #455-3140-ND. It's a 6 inch cable with a 6-pin socket on each end. Cut it in half and you have two 6-pin sockets.
Enjoy!
Last edited:
$3.00 for one board international should do it. Add $1.50 for an additional board (US or international). Initially I would like to limit each person to 2 boards in case others get interested later.
Ern,
Just a public "thanks" ...... my boards have arrived safely (and swiftly) in Europe ..... now to populate them.
If you have the time, could you indicate how you had the boards fabricated? I guess you picked up the "artwork" on the freeUSBi site and sent it to a PCB fabricator, but do you use an international source or a local one?
Anyroad thanks again for your community minded spirit
Just a public "thanks" ...... my boards have arrived safely (and swiftly) in Europe ..... now to populate them.
If you have the time, could you indicate how you had the boards fabricated? I guess you picked up the "artwork" on the freeUSBi site and sent it to a PCB fabricator, but do you use an international source or a local one?
Anyroad thanks again for your community minded spirit
Hi all,
I just noticed that the Sure web site is showing a couple other programming options now. One says it's an open source programmer for Sigma Studio ($14.90), and another one is called out as an In-circuit Programmer for the ADAU1701 ($19.90). No pictures or other info though, so not sure what to make of them.
I just noticed that the Sure web site is showing a couple other programming options now. One says it's an open source programmer for Sigma Studio ($14.90), and another one is called out as an In-circuit Programmer for the ADAU1701 ($19.90). No pictures or other info though, so not sure what to make of them.
There is also a reference to an "application version" priced $9.90, though it's not available in any of the selections. It would be really cool if they came up with a simpler, cheaper version with terminal connectors for 2 inputs and 4 outputs as well as power and programming connectors and nothing else.
I'm new to DSP but the product description was the cause of much of my confusion.
I found several options for the board on sure-hifi's eBay ad. Click the Model button on their ad to reveal these options:
- The default looks like the DSP board alone for $9.90 USD, this might be the application version.
- The Extension option is $9.90, suggesting maybe just the audio board.
- The Kernal option is the same package (kernal board + audio extension board) as found on their home website for $19.90.
- They also offer a programmer for Sigma Studio for $14.90 USD.
- Another option is an in-circuit programmer for $19.90 USD
ADAU1701 Audio Digital Signal Processor 3in 2out control DSP board | eBay
Ditto.ravels said:
Cheers, Art
Last edited:
I've always had trouble finding that board on their site using their search tools. But if you use Google with "Sure ADAU1701" it shows that the product is listed under Home / Audio / Digital Audio Generator and Microphone (why???). Then click on the picture to find the page with the interface board, cables, etc. Direct link:
Sure Electronics' webstore ADAU1701 Audio Digital Signal Processor Kernel Board
I haven't gotten too far yet, but there will be a detailed tutorial on Audiodevelopers.com on how to program the board using a micro rather than the boot EEPROM/programmer. There are several articles already posted that provide the background. Details and code are coming.
I finally got a "user" manual from the Sure EBay store. Not a lot of information that we don't already know, but it does have useful information about the In-Circuit Programmer and SigmaStudio Programmer. The user manual is a PowerPoint file and is too large to post here. I also converted it to PDF format - it's distorted a bit, but still readable. I put both in my Dropbox:
Powerpoint File
PDF File
Ed
Powerpoint File
PDF File
Ed
Based on my experience with other sellers/listings, I think the $9.90 default price is just the price of the cheapest option in the listing, which would be the extension board.
Thanks for sharing ED - I still have not received my items from Sure but this information will help a lot later on.