Design Con 2015
Breaking News
Comments
Newest First | Oldest First | Threaded View
elektryk321
User Rank
Rookie
re: Configure FPGAs over USB
elektryk321   8/30/2012 2:05:18 PM
NO RATINGS
I have seen project where FPGA device was able to reprogram bootrom (in this case EEPROM). There was only problem if the EEPROM or FPGA bitstream was broken wrongly written and FPGA won't start and reprogramm memory. I think USB debug interface in FPGA is stupid idea, JTAG is enought to do anything, and additional cost of USB-JTAG programmer is quite low. Of course if you want to have this capabilities just use small USB processor (like Cypress or Microchip) or FTDI USB chip, to do bit-bang emulation of JTAG or program bitstream memory.

Gopalakrishnan V
User Rank
Rookie
re: Configure FPGAs over USB
Gopalakrishnan V   8/25/2012 2:58:12 PM
NO RATINGS
Dear Eric, If an FPGA comes with "connector-ready" USB functionality inside it, then there are no cost added to your application design. I am not sure whether there are any FPGAs which comes with built-in USB functionality. In case of design where you need to add an USB functionality to the FPGA, more than the FPGA space, cost of USB IP to handle the protocol(either buying the IP or time involved in developing the IP) and external USB transceiver chip get added to your design cost and it becomes more expensive. USB protocol in itself is a complex implementaion unlike other communication protocol like SPI, I2C,etc. Please email me in gopv@cypress.com or gopalakrishnan.vijay@gmail.com if you have clarification questions or doubts regarding the USB protocol implementation in FPGA. As stated in the article, only the design where an USB interface is already a requirement for general data transfer, this method would be a cost effective solution. I apologize if the article does not convey this information directly. You are right that if USB data interface is never an requirement to the project, then there are lot many simpler and cost effective methods like JTAG that can be used for programming.

ewertz
User Rank
Manager
re: Configure FPGAs over USB
ewertz   8/25/2012 5:12:42 AM
NO RATINGS
"got flog" ... "got to flog" "If don't" ... "If you don't". Text, replace yourself above.

ewertz
User Rank
Manager
re: Configure FPGAs over USB
ewertz   8/25/2012 4:36:46 AM
NO RATINGS
If there was already "connector-ready" USB functionality inside the FPGA, there wouldn't be need for any intermediary device. The article stated as a given that this was an expensive use of FPGA resources -- a statement which you can separately debate depending on how much FPGA meat you've got flog. I think that the point here is that, in lieu of hard or soft USB functionality inside the FPGA, that such a scheme can be used as a bi-directional USB interface for both bitstream downloading as well as a USB Device (and perhaps Host) interface when the FPGA is running. The interface from the FPGA to the bridge chip can be anything from 1-bit serial to N-bit parallel, because the bridge chip is programmable with a decent number of I/O pins. I concede that I don't know what all the USB Blaster is capable of, but my understanding is that it was merely a barebones programming device. *If* it could be made to do anything useful post-programming, it would have to come back (in this case, the JTAG channel) out through the fairly dumb serial (or custom) driver on the host. I think the point is that if you both want a direct USB interface for both programming and execution (starting at 10s Mb/sec), then this is one such solution. If don't care about USB for both uses, then yes, you can do with less.

CMathas
User Rank
Blogger
re: Configure FPGAs over USB
CMathas   8/24/2012 6:24:52 PM
NO RATINGS
Thanks for the post, I'm alerting the author--stay tuned.

green_ee
User Rank
Rookie
re: Configure FPGAs over USB
green_ee   8/24/2012 5:11:38 PM
NO RATINGS
If there was a complete "connector-ready" USB endpoint on the FPGA device, I would say it's the coolest device I've seen all year. But it doesn't have this. A USB-blaster connected to an Altera device accomplishes the same thing, and an onboard controller with a JTAG interface would effectively do the same.



Top Comments of the Week
Flash Poll
Like Us on Facebook

Datasheets.com Parts Search

185 million searchable parts
(please enter a part number or hit search to begin)
EE Life
Frankenstein's Fix, Teardowns, Sideshows, Design Contests, Reader Content & More
<b><a href=Betajet">

The Circle – The Future's Imperfect in the Present Tense
Betajet
5 comments
The Circle, a satirical, dystopian novel published in 2013 by San Francisco-based writer Dave Eggers, is about a large, very powerful technology company that combines aspects of Google, ...

Max Maxfield

Recommended Reads From the Engineer's Bookshelf
Max Maxfield
31 comments
I'm not sure if I read more than most folks or not, but I do I know that I spend quite a lot of time reading. I hate to be idle, so I always have a book or two somewhere about my person -- ...

Martin Rowe

Make This Engineering Museum a Reality
Martin Rowe
Post a comment
Vincent Valentine is a man on a mission. He wants to make the first house to ever have a telephone into a telephone museum. Without help, it may not happen.

Rich Quinnell

Making the Grade in Industrial Design
Rich Quinnell
16 comments
As every developer knows, there are the paper specifications for a product design, and then there are the real requirements. The paper specs are dry, bland, and rigidly numeric, making ...

Special Video Section
The LT8640 is a 42V, 5A synchronous step-down regulator ...
The LTC2000 high-speed DAC has low noise and excellent ...
How do you protect the load and ensure output continues to ...
General-purpose DACs have applications in instrumentation, ...
Linear Technology demonstrates its latest measurement ...
10:29
Demos from Maxim Integrated at Electronica 2014 show ...
Bosch CEO Stefan Finkbeiner shows off latest combo and ...
STMicroelectronics demoed this simple gesture control ...
Keysight shows you what signals lurk in real-time at 510MHz ...
TE Connectivity's clear-plastic, full-size model car shows ...
Why culture makes Linear Tech a winner.
Recently formed Architects of Modern Power consortium ...
Specially modified Corvette C7 Stingray responds to ex Indy ...
Avago’s ACPL-K30T is the first solid-state driver qualified ...
NXP launches its line of multi-gate, multifunction, ...
Doug Bailey, VP of marketing at Power Integrations, gives a ...
See how to ease software bring-up with DesignWare IP ...
DesignWare IP Prototyping Kits enable fast software ...
This video explores the LT3086, a new member of our LDO+ ...
In today’s modern electronic systems, the need for power ...