OpenSDA on Vybrid

[anthony_huereca]

OpenSDA is a low‐cost debug/programming interface embedded in certain Freescale evaluation boards. It handles debug communications between the PC and target via USB. It uses a Kinetis K20 50Mhz chip on the bottom of Vybrid tower board to run firmware developed by P&E that acts as a bootloader. This lets it run and load "apps" that add functionality to the OpenSDA circuit. For example, an app could allow debugging with DS‐5, or IAR. Or an app could turn OpenSDA into a virtual serial port so you can get serial data via a USB cable instead of using a RS232 cable. Or an app could allow drag‐and‐drop programming of flash devices like QuadSPI. The possibilities are very open ended. This is the same OpenSDA circuit found on Kinetis L boards.

The app will run every time power is applied to the OpenSDA circuit via J3.

To load a new app, hold down the reset button (SW3) while power is applied via J3, then the firmware will enter a bootloader mode, and enumerate as a mass storage device. You can then drag and drop the new "app" into that MSD to load it. Power cycle the device, and then the new app will run.

Currently there are two apps available for Vybrid:

• CMSIS‐DAP ‐ For debugging with DS‐5 (default app on Rev A-F)
• Virtual Serial Port ‐ For creating a serial‐to‐usb bridge (default app on Rev G)

In the future there will be a Mass Storage Device (MSD) app that will include virtual serial port capability, plus enumerate as a mass storage device on your computer to drag‐and‐drop binaries to be programmed into QuadSPI, NAND Flash, and more.

Other things to note:

• Only RevG boards will have OpenSDA firmware
• All other revisions (except RevA) only have a basic CMSIS‐DAP firmware loaded onto the K20, and does *not* have the OpenSDA firmware/bootloader. Older boards cannot be upgraded since this firmware can only be loaded at the board manufacturer. RevA boards do not have either firmware.
• The OpenSDA circuit is only on the Vybrid tower board (TWR‐VF65GS10) and not other Vybrid boards.
• The OpenSDA bootloader firmware is proprietary. However some of the apps, like the CMSIS-DAP app, have source available and can be programmed stand-alone into the K20 circuit. This may be useful if developing your own board.
  • However note that this connection will be noticeably slower than using a dedicated debugger like D-Stream or JLink.

More information on OpenSDA can be found at:

http://www.pemicro.com/opensda

http://cache.freescale.com/files/32bit/doc/user_guide/OPENSDAUG.pdf

[kef2]

adiroot,

LASTSTAT in my kit is the same like yours
.

Regarding using Vybrid Tower kit debugger interface with DS-5 under Windows. It is too slow to be good, but since I don't know what to choose for good multivendor-ARM-debugger interface, I keep using what I have in Vybrid Tower.

Slowlyness is not the worst feature of this debugger. Connection to debugger SW is often problematic. My final app will boot from QSPI. Until I wasn't using data cache, debugger was able to connect with boot switches set to QSPI. After I enabled data cache and installed app to QSPI, I have no chances to connect until I change boot config! So I'm installing/removing one jumper, which swtiches from QSPI boot to SD boot (SD card is removed). This allows to connect. Then I hit reset and hit run from main() button each time after every compile. Each operation takes some time, so sometimes I forget to hit reset or reload app...

Sometimes it also needs closing/restarting DS-5 and/or replugging USB connected.

[pato3]

Switching toolchain is never an easy decision and I'm not using Linux so what can or cannot be done for Linux has to be investigated but Crossworks has just released V3.0.1 this week which supports the Vybrid and you might want to check it out, it's got a 30-day evaluation period.

Personally I've been using the Crossworks RC1 version heavily for the past 3 to 4 months on my Tower Board and my Cosmic+ and I'm very happy with it: fast, reliable and a sleek user interface.

[kef2]

Thanks, but I was wondering about JTAG that could be used not only with Vybrid, but also with ARMs from different vendors. It there such one? Switching toolchains isn't hard, just very annoing.  

[kef2]

• To load a new app, hold down the reset button (SW3) while power is applied via J3, then the firmware will enter a bootloader mode, and enumerate as a mass storage device. You can then drag and drop the new "app" into that MSD to load it. Power cycle the device, and then the new app will run.

I had to do it today for my new tower kit. It wasn't as simple as above. Entering bootloader was simple like expected. But I tried to copy CMSIS-DAP.S19 to bootloader and disconnecting/connecting USB cable many times without success. LASTSTAT.TXT kept showing Ready and Ready again and again.

Then I tried replugging data plug of dual USB-A end of the cable. Hooray, "Completed" in LASTSTAT.TXT, power cycle and DS-5 debugger connects. So something is wrong with OpenSDA bootloader documentation.

[naoumgitnik]

Small correction - "Only RevG or newer boards will have OpenSDA firmware".

/Naoum Gitnik.