FAQ (Blackfin®)

From BlueWiki

Jump to: navigation, search


1 Blackfin® FAQ

1.1 Which versions of BLACKSheep® OS support Ethernet?

At CM-BF533 and CM-BF561 the DEV-BF5xx version supports the SMSC chip.
At CM-BF537 all versions supports the internal MAC.
At TCM-BF537 the DEV-BF5xx version supports the SMSC.
At TCM-BF518 the DEV-BF5xx version supports the SMSC and the Ethernet PHY.

1.2 What are the TCP/IP settings for BLACKSheep® OS supporting Ethernet?

BLACKSheep® OS is preconfigured with the IP-Address and default MAC-Address AC:DE:48:01:02:03
Open a command line at your PC and type "ping" to check the Ethernet connection to the core module.
Currently all core modules are shipped with the same MAC-Address! Connecting more than one
module to the same network may create problems!

1.3 Can I flash a new BLACKSheep® OS version without having a JTAG device?

Yes you can! First copy the latest BLACKSheep® OS loader file to your core module using the "xmt" command on the
BLACKSheep® OS console. Then use the "flash" command to flash the new version. Refer to the BLACKSheep® OS "Command Reference Manual"
to learn more about the BLACKSheep® OS commands.

1.4 Which JTAG devices are supported by the core modules?

The core modules support all Blackfin® compatible JTAG devices.

1.5 I get error messages while downloading examples with a JTAG device. What is wrong?

Be sure you have updated the xml-files in the "ArchDef" directory at the installation path of the VDSP++.
The settings within the xml-files are for the EZ-KIT LITE from Analog Devices. These boards have different SDRAM settings.
VDSP++ uses these settings to initialize the SDRAM during the startup of VDSP++. Download the modified xml-files from the Customer Software Download area.
Rename the old files and copy the new one in the directory. Be aware that the EZ-KIT is not working
anymore with the new settings.

1.6 Why does BLACKSheep® OS crashes during a flash erase process on some modules?

The flash maybe is locked per default. Type "flash -unlock" prior to start an erase process.

1.7 How can I flash the uboot HEX-file?

Without JTAG device
Connect to the core module using a terminal program like Hyperterminal under Windows
or minicom under linux.
At the BLACKSheep® OS console type "xmr filename". Start uploading the uboot hexfile
via your terminal programm using the xmodem protocol.
Type "flash -rsdev" to erase the flash device.
Type "flash filename -b" to flash the hexfile.
Change the boot mode to "00". Refer to the Hardware User Manual of your eval or dev
board to see how to change the boot mode.
After the next reset or power on the uboot boot screen should appear.
See next question to learn how to flash uboot without overwriting the BLACKSheep® OS
boot loader.
Refer to the BLACKSheep® Command Reference manual to learn more about the BLACKSheep® OS
Using a JTAG device
Refer to the appropriate flash tool description for your JTAG device.

1.8 Is there a possibility to flash uboot without overwriting BLACKSheep® OS and changing the boot mode?

Yes there is. After uploading the uboot HEX-file type "flash filename -a" at the
BLACKSheep® OS console. uboot will be flashed as an application without overwriting
BLACKSheep® OS. After this you can start uboot by typing "load 1 -de".

1.9 What are the main differences between the core module CM-BF537E/U and TCM-BF537?

CM-BF537E is equipped with an on-board physical Ethernet chip, SDRAM and flash.
CM-BF537U is equipped with an on-board USB2.0 device chip, SDRAM and flash.
TCM-BF537 is equipped with on-board SDRAM and flash.
CM-BF5xxx: 2MB of J3 flash
TCM-BF537: 4 or 8 MB of P30 flash, depending on the revision
Temperature range
CM-BF5xxx: consumer
TCM-BF537: industrial
CM-BF5xxx: 31.5 x 36.5mm
TCM-BF537: 28 x 28mm

1.10 What can I do if I get a linker error like: "Address out of range for UserExceptionHandler"?

This can occur at VDK projects with extensive use of internal L1 code memory.
There exist a limit at Blackfin® processors regarding the range of relative jumps.
The TMK532 lib jumps to the user exception handler at an error condition. This error occurs when the TMK library
resides in internal memory and the UserExceptionHandler does not. e.g. it is located in the external memory.
The UserExceptionHandler is declared in the ExceptionHandler-BF5xx.asm file which is part of all
VDK projects. Just modify the file to force the symbol to the internal code memory with an appropriate
section directive. This should eliminate the linker error.

1.11 How large can loader files be for booting at the Blackfin® core modules?

First of all this strongly depends on the used core module.
Be aware that the loader file created with VDSP++ can be quite larger than the size occupied in flash,
depending on the used file format.
The sizes below means the size occupied in flash not the file size!
CM-BF53x, TCM-BF537, CM-BF527 and TCM-BF518
CM-BF561, CM-BF561V2 and CM-BF548
Equal to flash size
If the loader file exceeds the limits above, a special second stage boot loader is needed.
Be aware that these limits are only vaild if you are using Bluetechnix initialisation files to create the loader files.
The limits can be smaller if you dont use an initialisation file or you are using your own files.
At the CM-BF53x, TCM-BF537 and CM-BF527x the second asynchronous memory bank has to be enabled
by the initialisation file otherwise the internal Blackfin® boot loader cannot access it.

1.12 Why do I get an error (-7: Flash not empty) while flashing a new HEX-file with the flash command of BLACKSheep® OS , even when the flash is empty?

Unfortunately there are two versions of BLACKSheep® OS available containing a bug at the flash driver: version "EVAL-BF5xx 0.5.1 build Jul 14" and version "EVAL-BF5xx 0.5.1 build Jul 18".
If your core module is flashed with one of these versions please update your BLACKSheep® OS using the update tool located at the software download section.
Follow the instructions given in the readme.txt file. Type "ver" at BLACKSheep® OS console to verify which BLACKSheep® OS version is flashed on your core module.

1.13 Why does BLACKSheep® OS not boot when I do not connect an USB cable to the UART-USB bridge of the EVAL-BF5xx Board?

Only valid for development borads with revision <= 4.0.
BLACKSheep® OS uses the UART as terminal interface. The UART is connected to the USB-UART bridge per default.
If you do not connect an USB cable the USB-chip is not powered and produces undefined behavior at the UART RX pin.
This causes a malfunction of the BLACKSheep® OS boot loader. If you want to boot BLACKSheep® OS without an USB cable connected, set the switch SW1 to route the
signals to the UART pads as described in the Hardware User Manual of the EVAL-BF5xx Board.

1.14 Possible thermal problems on CM-BF561

On some CM-BF561 there can be thermal problems if the core voltage is set above 1.3VDC.
The internal voltage level in the VR_CTL register does not match the effective voltage on the VDDint pin of the BF561.
There is a difference of about 80mV. This means that the maximum value for VLEV in the VR_CTL register can be "1101".
Older versions of BLACKSheep® OS (< 0.5.2) ignore this issue. Newer versions can be downloaded from the Customer Software Download area.

1.15 My VisualDSP++ USB-ICE emulator environment has suddenly stopped working with the CM-BF5xx Core Module and EVAL-Board

A corrupt flash code can prevent JTAG operation. If you have flashed your own application onto the module, it is possible that the flash content is
corrupted and this leads to an undefined behaviour of the core modules. This can be the reason why you cannot connect via JTAG anymore.
Change the boot mode of your core module to overcome this problem.
Personal tools