📬❄️📦Adafruit Holiday Shipping Deadlines 2019: Please place all UPS 3 Day orders by 11am ET Friday December 13 📬❄️📦
0

USB to JTAG programmer?
Moderators: adafruit_support_bill, adafruit

Please be positive and constructive with your questions and comments.

USB to JTAG programmer?

by echoskope on Thu Apr 01, 2010 9:46 pm

So for my digital electronics class we have working with Altera UP2 University boards (using the MAX7000S CPLD), and the only way to program them is using a jtag programmer (the "bit banger"). Of course this is no problem if you have a parallel port, but, of course, my laptop does NOT have a parallel port and since I do alot of programming on my laptop through Quartus II for our project I would like to be able to program the board via USB. So far all of the adapters I have found are insanely expensive (at least the ones Altera sell are), and always say they are for speicfic chips. Heres where I am stuck: I thought jtag was an IEEE standard, so doesn't that mean its universal and even if I buy a USB -> JTAG programmer thats sold as an "ARM processor programmer" I should still be able to use it to program my CPLD? What is it that makes it expensive to change USB to serial to parallel to jtag?

Thanks!

echoskope
 
Posts: 31
Joined: Fri Nov 13, 2009 10:08 pm
Location: Edmond, Oklahoma

Re: USB to JTAG programmer?

by johngineer on Thu Apr 01, 2010 10:00 pm

It depends. The JTAG communications model is standardized, i.e. what the pins are for and what they're called, but the physical connectors differ from one manufacturer to the next.

ARM uses a 2x10 pin connector, TI uses a 2x7, Altera uses a 2x5.

You'd be better off getting a USB-Parallel Port adapter and using it with the programmer you already have.
Adafruit Director of Imaging
Member of Technical Staff
Poles up, zeroes down.
johngineer
 
Posts: 105
Joined: Fri Aug 14, 2009 6:05 pm
Location: Brooklyn, NY, USA

Re: USB to JTAG programmer?

by echoskope on Thu Apr 01, 2010 10:31 pm

Thanks for the reply!

Even though its a different size connector could you not just run wires from the connector to a breadboard and then to the right sized connector? (just rearranging the pins in the right order)? I thought about the USB -> Parallel but those seem to be hard to come by. I have found USB -> LPT port adapters, but no luck with a USB parallel port emulator that can I could program with :( maybe I am just not looking in the right direction...

echoskope
 
Posts: 31
Joined: Fri Nov 13, 2009 10:08 pm
Location: Edmond, Oklahoma

Re: USB to JTAG programmer?

by johngineer on Thu Apr 01, 2010 11:54 pm

echoskope wrote:Thanks for the reply!

Even though its a different size connector could you not just run wires from the connector to a breadboard and then to the right sized connector? (just rearranging the pins in the right order)? I thought about the USB -> Parallel but those seem to be hard to come by. I have found USB -> LPT port adapters, but no luck with a USB parallel port emulator that can I could program with :( maybe I am just not looking in the right direction...


I suppose you could. To be honest, I don't know enough about the ARM or Altera connectors to give a definitive answer. I just know from my own experience that trying to use an AVR programmer on a TI JTAG header doesn't work all that well. :)
Adafruit Director of Imaging
Member of Technical Staff
Poles up, zeroes down.
johngineer
 
Posts: 105
Joined: Fri Aug 14, 2009 6:05 pm
Location: Brooklyn, NY, USA

Re: USB to JTAG programmer?

by charliex on Sat Apr 03, 2010 2:59 pm

You'll probably never find a usb->parallel that work with any kind of bit bang, they're usually for printers only. Centronics to usb vs a parallel to usb.

Some of the cardbus printer adapters have been known to work.

JTAG is like JPEG in that its a joint standard, but there are different standards, variations and extensions. So your jtag adapter and software has to support the CPLD you're programming.

check out the wiggler see if it does cpld's.
http://032.la - Null Space Labs.
charliex
 
Posts: 179
Joined: Sat Nov 28, 2009 5:54 pm
Location: Las Vegas

Re: USB to JTAG programmer?

by fat16lib on Sat Apr 03, 2010 8:22 pm

The USB interface for JTAG programmers/debuggers is not standardized. You need to get a USB to JTAG cable that Quartus II understands. It will probably cost a bit. Here is one that seems reasonable priced. I have not used it.

http://www.cutedigi.com/product_info.php?products_id=4339

I have had a lot of problems with USB drivers for JTAG programmers for my X64 Windows 7 notebook so make sure there are good drivers if you have an X64 system.

I don't think any low priced USB to ARM JTAG cable will work.
fat16lib
 
Posts: 593
Joined: Wed Dec 24, 2008 1:54 pm

Re: USB to JTAG programmer?

by westfw on Sat Apr 03, 2010 8:33 pm

There are some theoretically generic USB/JTAG adapters. For example, the Luminary (now TI) Cortex-M3 eval kits (some of which are relatively inexpensive) are all supposedly capable of being used as JTAG adaptors for their chips. However, there remain several problems:

1) The data/commands that you have to send to a JTAG port to accomplish something specific are very varied. By its very nature even the bit-length of each command can be different for each chip, or different for a chip within one system vs another (JTAG, as I understand it, essentially makes big; long; shift register chains of assorted device internal registers. And you can chain multiple devices together so that a board with multiple JTAG devices only needs a single JTAG port.

2) There doesn't seem to be a standard communication protocol over USB to JTAG (as there is for mass storage, for example), so each USB/JTAG device is somewhat different (and of course has different USB Vendor/device identifiers.)

These combine to mean that typically a given manufacturers software only works with THEIR usb/jtag hardwre :-(
westfw
 
Posts: 1585
Joined: Fri Apr 27, 2007 1:01 pm
Location: SF Bay area

Re: USB to JTAG programmer?

by unwiredben on Sun Apr 04, 2010 10:43 am

You might want to look at the the really cool Bus Pirate board that does USB-to-all-sorts-of-things. Here's their article JTAG interfacing with it - http://dangerousprototypes.com/bus-pira ... tag-guide/

unwiredben
 
Posts: 75
Joined: Fri Dec 19, 2008 2:02 pm
Location: Brooklyn, NY

Please be positive and constructive with your questions and comments.