Open JTAG Emulator devices

[ericengler9]

Posted on February 13, 2009 at 10:37

Open JTAG Emulator devices

[ericengler9]

Posted on May 17, 2011 at 12:23

I know of 2 open hardware USB JTAG devices that are friendly to OpenOCD: The Olimex Arm-USB-OCD and the Amontec JTAGKey. I strongly prefer USB devices over wigglers because they're faster and most people don't have parallel ports any more.

There is an open Windows driver for gdb that uses the Jlink device, and it's called the JlinkServer. Actually, the driver itself is closed, but it's free and it has an open API that gdb can work with. I don't know for sure if this driver will work on the STM32. And it defintely won't work in the SWD mode.

I don't know of any open source driver for the popular Ulink JTAG emulators. This is a bummer because I have several of these. They only work with the Keil/Arm toolchain.

Likewise, I don't know of any open drivers for the Raisonance Rlink USB emulator. If you own either a Ulink or and Rlink you're out of luck with open source.

I wondor if Olimex or Amontec would consider supporting the SWD debugging mode on the Cortex M3, or if another company would make this kind of device for USB and SWD?

The best forum that is specifically for OpenOCD is the Sparkfun forum. But most people there aren't using the Cortex M3.

Now that NXP has announced Cortex M3 chips for late in 2008, that might generate more interest in this core. Maybe some Arm7 people will start looking at the STM32 now. It seems like the M3 is heading for success, and the STM32 and Luminary Stellaris might benefit because they are already in this space.

Eric

[vlaladim]

Posted on May 17, 2011 at 12:23

Hi

I think I have a solution for you

I am working on a project that will fit your needs, if you want contact me

Vlad

[e-mail]

[sjo]

Posted on May 17, 2011 at 12:23

There are quite a few open source usb jtag tools about, not just Amontec/Olimex.

Infact the original design was done as part of Dominic Rath's thesis, they are pretty much all based on the ftdi chip.

They have just taken the open design and made a few changes. The software openocd is worked on by volunteers, so Olimex or Amontec would probably be the last place to go for adding SWD support.

There are no plans for SWD support in openocd using the ftdi chipset, it is too limited. This may change but unlikely.

I have started work on a STM32 based jtag dongle but work commitments are delaying the progress.

Cheers

sjo

[sjo]

Posted on May 17, 2011 at 12:23

i was talking about the ftdi chip.

we have a patch for openocd that uses the swd interface using a ftdi chip but it still requires a lot of work. If interested it is in the mailing list archive:

http://https://lists.berlios.de/pipermail/openocd-development/2008-November/003742.html

Cheers

Spen

[st3]

Posted on May 17, 2011 at 12:23

Quote:

There are no plans for SWD support in openocd using the ftdi chipset, it is too limited.

Which one is ''too limited'' - the SWD, or the FTDI device?

Or both?