• 0
Sign in to follow this  
enliteneer

Software won't recognize AD2

Question

I recently received the AD2, but having terrible luck getting Waveforms (3.8.2) to see the hardware. 

I've installed/re-installed on numerous laptops (winxp, win7, win8, and win10), and the error is usually one of the following,

1) On the WinXp, 7, and 8 machines, I see the error : Post AVCC Device configuration failed and to try powering with the aux input  

When I plug 5V into the aux barrel jack, the AD2 usually loses the usb connection immediately (device manager removes the 'USB Serial Converter' entry).  But even when it doesn't lose the usb, Waveforms still reports the Post AVCC error message

2) On the Win10 laptop, I don't get the AVCC error, however, when I click any of the functions (Scope, Wavegen, etc) it pops up with a "Communication with the device failed"                                           

Interestingly, in all cases the software lists the Serial Number and I'm able to select it, so I'm assuming the driver is ok.   Also just plugging in 5v to the aux power, I'd expect *some* led activity, but I don't see anything.   Only when the usb is plugged , and Waveforms has the error message, do I see an led blink (~500msec) near the center of the board.

I'm assuming the hardware gets tested before it ships, so it's something on my end, but after a week of trying, I have no idea what the problem is... it shouldn't be this hard, right?

Share this post


Link to post
Share on other sites

10 answers to this question

Recommended Posts

  • 0

Hi @enliteneer

Make sure the 5V DC supply is properly regulated. The AD2 device accepts AUX supply voltage in range of 4.11 - 5.76V.
https://reference.digilentinc.com/reference/instrumentation/analog-discovery-2/reference-manual#usb_power_control
You could also try using powered USB hub.

The only led in the device is controlled by software, which blinks only during and after the application connects to the device.
Yes, each device is tested and calibrated during the manufacturing process.

Share this post


Link to post
Share on other sites
  • 0

I hooked up a voltage/current monitor in-line with the AD2, and aside from a brief 10ma blip when I open the application,  it doesn't seem to ever draw any power. 

 

Not sure what else to do at this point, is this the official way to get support for digilent products?  I don't see any tech support email on the Digilient site.   

 

Edited by enliteneer

Share this post


Link to post
Share on other sites
  • 0

Hi @enliteneer

If I see right in the video you have connected the auxiliary 5VDC to a USB hub/supply.
Please try to connect only the USB to a powered USB hub, without AUX supply.

Share this post


Link to post
Share on other sites
  • 0
On 7/9/2018 at 6:05 AM, attila said:

Hi @enliteneer

If I see right in the video you have connected the auxiliary 5VDC to a USB hub/supply.
Please try to connect only the USB to a powered USB hub, without AUX supply.

Thanks, you are correct I was trying to supply power via the aux 5VDC.   If I try to connect only to one of the laptop's usb3 ports, I get the error in this attached image:

Although sometimes, I don't get that power error, but instead get the communication error shown in the previous gif.

The usb shows to be drawing around 140ma-170ma..  using the cable that came with the AD2, but I've tried 3 others with the same result.

Unfortunately, I don't have a powered usb hub to try, but I can order one...     however, shouldn't the aux connector on the AD2 do the same?

usb.png

Share this post


Link to post
Share on other sites
  • 0

Hi @enliteneer

I suspect the 5V DC supply you are using can't provide suffice power. It is recommended to use 5V/2.5A supply.

On 7/2/2018 at 3:19 PM, attila said:

Make sure the 5V DC supply is properly regulated. The AD2 device accepts AUX supply voltage in range of 4.11 - 5.76V.
https://reference.digilentinc.com/reference/instrumentation/analog-discovery-2/reference-manual#usb_power_control

Share this post


Link to post
Share on other sites
  • 0

The power strip has a built-in 5V 1A regulator, and shows very little ripple when measured by the bench scope..  I don't have a 2.5A usb charger, but doubt that would make the difference since the top gif shows the AD2 only draws (briefly) 10ma via the aux power, when the application is executed.     Is there a momentary peak draw of over 1A?

Is there any suggestions for the phenomena of AD2 losing the usb connection  (device manager removes the 'USB Serial Converter' entry), whenever the aux barrel power is inserted?

Share this post


Link to post
Share on other sites
  • 0

Hi @enliteneer

I managed to reproduce a similar behaviour that you are seeing by supplying the AD2 from an adjustable supply with 500mA current limitation.

On AD2 the USB controller is always supplied from USB power. So the device should be removed from the device manager on USB disconnect or USB supply cut, like due to overcurrent protection...
Initially both the USB and AUX are enabled to supply the rest of the device. After connection having 5V AUX plugged the supply from USB is stopped for the rest of the board. I suspect at this moment your 5V supply can't provide suffice power, the voltage drops and the device is reset.

You can try installing WF v3.8.7:
https://forum.digilentinc.com/topic/8908-waveforms-beta-download/
In the device manager right click to open the menu and check the "Simultaneous supply" or "Keep the USB Supply always ON" option.
With this, both the USB and AUX supplies will be enabled to supply the device.

image.png.c75e2907b433c9f4a90c253b2f6e7f6f.png

 

Edited by attila

Share this post


Link to post
Share on other sites
  • 0
On 7/25/2018 at 12:07 AM, attila said:

Hi @enliteneer

Is the device working for you now?

Thanks, I was still getting errors, but I then downloaded version 3.8.8 and selected 'Don't Stop The Device on Disconnect' and then it worked!     Thank you for the help!

Power.png

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this