Forums

BlackFin USB

Started by Vladimir Vassilevsky April 27, 2011
I am experiencing very unreliable operation of the AD BlackFin BF-527 
USB port (host mode, high speed). It seems to be a hardware problem. Did 
anyone accomplish a successful operation of the BlackFin USB port as a 
high speed host mode?

There is the USB_RSET pin on the port, which presumably sets the output 
current and/or termination of the USB. The datasheet is vague on the 
purpose and the connection of this pin. The AD support is silent. Do you 
know what could this pin be (may be, by analogy with the other USB 
controllers) ?


Vladimir Vassilevsky
DSP and Mixed Signal Design Consultant
http://www.abvolt.com
On 27.04.2011 20:54, Vladimir Vassilevsky wrote:
> There is the USB_RSET pin on the port, which presumably sets the output > current and/or termination of the USB. The datasheet is vague on the > purpose and the connection of this pin. The AD support is silent. Do you > know what could this pin be (may be, by analogy with the other USB > controllers) ?
http://ez.analog.com/message/13942#13942 The odds are higher that you'll get answers on ADI DSP related questions fast if you post them on the Engineer Zone than if you send an e-mail to the ADI support. -- Alexander

Alexander Sotnikov wrote:
> On 27.04.2011 20:54, Vladimir Vassilevsky wrote: > >> There is the USB_RSET pin on the port, which presumably sets the output >> current and/or termination of the USB. The datasheet is vague on the >> purpose and the connection of this pin. The AD support is silent. Do you >> know what could this pin be (may be, by analogy with the other USB >> controllers) ? > > > http://ez.analog.com/message/13942#13942 > > The odds are higher that you'll get answers on ADI DSP related questions > fast if you post them on the Engineer Zone than if you send an e-mail to > the ADI support.
Here is the official answer from AD support: "The USB_RST pin should be connected to an unpopulated resistor as there may be a future advantage to this configuration" ...Whatever it could mean... Vladimir Vassilevsky DSP and Mixed Signal Design Consultant http://www.abvolt.com
On 4/28/2011 6:21 AM, Vladimir Vassilevsky wrote:
> > > Alexander Sotnikov wrote: >> On 27.04.2011 20:54, Vladimir Vassilevsky wrote: >> >>> There is the USB_RSET pin on the port, which presumably sets the output >>> current and/or termination of the USB. The datasheet is vague on the >>> purpose and the connection of this pin. The AD support is silent. Do you >>> know what could this pin be (may be, by analogy with the other USB >>> controllers) ? >> >> >> http://ez.analog.com/message/13942#13942 >> >> The odds are higher that you'll get answers on ADI DSP related >> questions fast if you post them on the Engineer Zone than if you send >> an e-mail to the ADI support. > > Here is the official answer from AD support: > > "The USB_RST pin should be connected to an unpopulated resistor as there > may be a future advantage to this configuration" > > ...Whatever it could mean... > > > Vladimir Vassilevsky > DSP and Mixed Signal Design Consultant > http://www.abvolt.com > >
Offhand, it sounds like they haven't the foggiest of what the actual behavior of the pin is, and are trying to keep their options open to be able to publish a fix in the errata docs. -- Rob Gaddi, Highland Technology Email address is currently out of order