I need to compile by simulink inside BB hardware a block that returns an .avi video signal like the 'From a Multimedia File' simulink block.
I tried to compile a simulink model with 'From a Multimedia File' block but building fails since, i think, it can not transfer "block + file" into BB.
How can i make it to out a video file signal as stand-alone application ?
Does the BB have any file I/O? Otherwise, it doesn't make sense at all to generate code for the block... The doc for the DSP block says:
This block supports code generation for the host computer that has
file I/O available. You cannot use this block with Real-Time Windows
Target™ software because that product does not support file I/O.
It also says that the "generated code for this block relies on prebuilt library files" and recommends using PackNGo to make sure all the dependencies are included in the generated code. If you haven't look at the documentation for the block yet, I strongly recommend that you do so.
Also, there is another block with the same name from the Computer Vision System Toolbox, which one are you referring to? Again, look at the doc, it has the same comments about requiring prebuilt library files.
I'm not sure whether the code generation will work with the BB target (note that the doc only mentions "host" computer as opposed to target), but the fact remains that the target does require file I/O otherwise it's a pointless exercise.
Related
I work on Linux kernel loadable module and I look for proper way to configure it and way to load/store binary data when module is loaded/unloaded. The module needs to read configuration data in time of loading, but it may change data and save them in run-time. I read on many places that reading/writing to file is not recommended and I also read that sysfs can be used for such purpose. Can be binary configuration data stored in sysfs ? Or exist more suitable solution ? Can you provide link to some example or doc where I can found some details about how to load/save persistent configuration by module ?
Peter
Maybe you can use the firmware interface in the module.
It should be able to load a binary file which include your settings with request_firmware(..)
I think it isn't required to write this binary file to the hardware...?
There are probably a lot of ways to do this. The way that leaps to my mind is with a character device and a script running in userspace. You could arrange that the script loads your module and then writes the binary data to the character device file created by the module. The script could proceed to loop on a read of the device file. When the module wants to export new state, it unblocks the read. The script then copies out the data, and repeats.
For my university project I'm doing a module which will allow or disallow a process to perform a system calls (e. g. A little loadable selinux). For now I nave code that controls syscalls. For each process I store a link to the structure which contains permissions config. However, now I've just hardcoded two configs: one is default (allow all) and another one is to allow everything except opening '/testfile'.
My question is how to load configs dynamically?
I have a parser for config files but I've read that accessing files from the kernel is bad idea.
How should I store configs and how should I load them?
I've read that reading files from the kernel is bad idea
Description of filp_open function in the kernel sources says:
This is the helper to open a file from kernelspace if you really have to. But in generally you should not do this, so please move along, nothing to see here..
So, if you need to load/store content of the file into/from the kernel module, then do that. But use appropriate functions, as described in that question.
I have a QSPI flash on my embedded board.
I have a driver + process "Q" to handle reading and writing into.
I want to store variables like SW revisions, IP, operation time, etc.
I would like to ask for suggestions how to handle the different access rights to write and read values from user space and other processes.
I was thinking to have file for each variable. Than I can assign access rights for those files and process Q can change the value in file if value has been changed. So process Q will only write into and other processes or users can only read.
But I don't know about writing. I was thinking about using message queue or zeroMQ and build the software around it but i am not sure if it is not overkill. But I am not sure how to manage access rights anyway.
What would be the best approach? I would really appreciate if you could propose even totally different approach.
Thanks!
This question will probably be downvoted / flagged due to the "Please suggest an X" nature.
That said, if a file per variable is what you're after, you might want to look at implementing a FUSE file system that wraps your SPI driver/utility "Q" (or build it into "Q" if you get to compile/control source to "Q"). I'm doing this to store settings in an EEPROM on a current work project and its turned out nicely. So I have, for example, a file, that when read, retrieves 6 bytes from EEPROM (or a cached copy) provides a MAC address in std hex/colon-separated notation.
The biggest advantage here, is that it becomes trivial to access all your configuration / settings data from shell scripts (e.g. your init process) or other scripting languages.
Another neat feature of doing it this way is that you can use inotify (which comes "free", no extra code in the fusefs) to create applications that efficiently detect when settings are changed.
A disadvantage of this approach is that it's non-trivial to do atomic transactions on multiple settings and still maintain normal file semantics.
I'm midway through a VHDL class and have been able to play relatively nice with the ISE and Digilent toolchain in Linux... until trying to reflash a PicoBlaze program. For details, I am currently running and targeting,
Fedora 21 64-bit (3.19.3-200.fc21.x86_64)
Nexys2 development board from Digilent (with a Spartan3)
Xilinx ISE 14.7
Adept 2.16.1 Runtime
Adept 2.2.1 Utilities
I've been able to run ISE and program the Nexys2 bit files with iMPACT just fine so far in Linux, but this current project is to write an assembly program for the PicoBlaze soft core processor, compile and update the memory of the running vector without having to resynthesize any VHDL.
Using the steps from Kris Chaplin's post, I can compile a PSM to HEX and then convert that HEX file to an SVF in dosbox. From here I can use Digilent's Adept tool in Windows to program a top_level.bit file which has the PicoBlaze already synthesized, I could also do this in ISE's iMPACT in Linux. After the design is running, I can use Adept to program the SVF file into the running memory of the design and everything is peachy. However, trying to load the SVF into iMPACT in Linux throws an exception,
EXCEPTION:iMPACT:SVFYacc.c:208:1.10 - Data mismatch.
The only issue I've found online with that error shows that there should be an '#' symbol that needs to be removed, but I haven't seen any '#'s anywhere in the SVF.
I also tried to convert the SVF to XSVF. iMPACT doesn't throw an error loading the XSVF, but programming/executing the XSVF freezes the design instead of running the new program.
Adept doesn't have a comparable GUI in Linux that I've seen, just a cmd line tool 'djtgcfg'. Just like iMPACT, I've been able to program the toplevel.bit file fine with
$ djtgcfg prog -d Nexys2 -i 0 -f ../../toplevel.bit
but attempting to program the svf file with the same call doesn't seem to affect anything. It says it should take a few minutes and immediately reports "Programming succeeded" but I don't see any change on the device.
I'd really like to keep my environment all in Linux if I can, I don't have quite enough room on my laptop to juggle between two VMs.
Is it possible to use use iMPACT to write an SVF file to the Nexus2? Or can/should I be using the Adept utility differently?
Has anyone gotten this to work? Thanks a ton!
There are many better ways to reconfigure the PicoBlaze InstructionROM without resynthesizing:
use Xilinx's data2mem tool
This toll is shipped with ISE and can patch BlockRAM contents in bit-files
=> requires FPGA reprogramming
use PicoBlaze's embedded JTAGLoader6
Enable the embedded JTAGLoader6 design in the template file. Use JTAG_Loader_RH_64 binary or JTAG_Loader_Win7_64.exe to upload a hex-file via JTAG into the PicoBlaze ROM.
=> reconfigure ROM at runtime, no FPGA reprogramming needed
The manual from Ken Chapman offers several pages on how to use JTAG_Loader. Additionally, have a look into the PicoBlaze discussions at forums.xilinx.com. There are some discussions regarding bugs and issues around JTAG_Loader and how to solve them.
Also have a look into opbasm from Kevin Thibedeau as an alternative and improved PicoBlaze assembler. It is also shipped with an ROM patch tool.
I know it's a little bit late for the original poster, but I suspect I am taking the same class and I believe I have found a solution to upload picoblaze code on linux.
Download the KCPSM3 zip file from Xilinx IP Download, extract the contents and move the executables from the JTAG_loader folder to your working directory.
In dosbox run hex2svfsetup.exe for the nexys2 board select menu options 4 - 0 - 1 - 8
Use the assembler to create the .hex file
In dosbox run hex2svf.exe to create the svf file
Then run svf2xsvf.exe -d -i < input.svf > -o < output.xsvf >
The contrary to the JTAG_Loader_quick_guide.pdf in the initial zip file use impact and open the xsvf file and program using the xsvf file.
I'm envisioning a program I will need to write and need some advice on the language. I will need to be doing raw disk access so I can display hex data, scroll or jump around on the disk, and do calculations from the data. I have been using Java the most and it's portability between OSes for my other projects is certainly a benefit, but raw disk access either isn't possible, would require JNI, or may be possible on *nix when you can access disks as "files". I keep reading different things. By the way I can handle this type of work using Files in Java, but in this project I need to be able to access the disk so disk imaging to files beforehand isn't needed.
It would be nice to make it as portable as I could since there is a real benefit to using different OSes, but it may not be worth it and I should just stick with Windows and a native compiling language. Is there any existing JNI code that could help? I have experience in other languages but I haven't used C++ in a long time. Should I forget about Java and tryout C#? Someone told me that Python has libraries available for this type of thing despite it being an interpreted language so what about Python? What would be best for the project? What would be good for me to learn?
Searching around for raw disk access, Java, Python, does not seem to give any useful results. Thanks for any help!
EDIT
It seems like this will be quite involved, learning what I need to know, and then learning that. It's too bad I couldn't use disk images instead because then I'd be able to start working on it immediately in Java, which I'm comfortable with and I know I could make a good product. I've gotten great throughput in other raw data processing projects with Java so that doesn't worry me. Plus it would be truly portable. Hmm might have to consider it more. I'd probably need a big azz storage system to hold all the images though :)
UPDATE
Just a note for anyone that finds this question... I have figured out this works just by specifying the disk for the File using the PhysicalDrive notation (in Windows) like the answer below by hunsricker. However there are some issues. First if you do a "exists" check File.exists(), it says the file does not exist. Also, the file size is zero, and when I get a "java.io.IOException: The drive cannot find the sector requested" is the way I know I'm at the end of the file. And the worst part- I was getting some odd runtime errors doing this when I was reading some bytes and skipping some (64) bytes in a loop. I altered my program a bit to read different amounts and that changed where the error occurred. I was using BufferedInputStream instead of RandomAccessFile like hunsricker below by the way, not sure if it makes a difference. My only answer for this issue is that since I'm doing physical disk access, it doesn't like that I am not reading in even 512 byte sectors or 1K blocks or such. Indeed when I read even 1K, 2K, 512bytes, etc., and don't skip anything, it works fine and runs to the end. The errors I saw were java.io.ioexception "incorrect function" and java.io.ioexception "the parameter is incorrect". There was no rhyme or reason to them. Then I made image files of the same data and ran my program on those and it would do any combination of reading and skipping bytes with no problem. Physical disk access was more picky I guess.
I was looking by myself for a possibility to access raw data of a physical drive. And now as I got it to work, I just want to tell you how. You can access raw disk data directly from within java ... just run the following code with administrator priviliges:
File diskRoot = new File ("\\\\.\\PhysicalDrive0");
RandomAccessFile diskAccess = new RandomAccessFile (diskRoot, "r");
byte[] content = new byte[1024];
diskAccess.readFully (content);
So you will get the first kB of your first physical drive on the system. To access logical drives - as mentioned above - just replace 'PhysicalDrive0' with the drive letter e.g. 'D:'
oh yes ... I tried with Java 1.7 on a Win 7 system ...
RageDs link brougth me to the solution ... thank you :-)
Disk access will depend on the disk's particular drivers. And since this is such a low-level task, I doubt Java/Python would have such support (these languages are generally used for fast, high-level software package development). Since you will probably not be aware of the disks' particular hardware implementations, you will probably have to end up using an operating system API (which is OS-dependent of course). I would recommend looking into C and/or the particular assembly language for the architecture you plan to do this work on. Then, I would recommend continuing your search to find the appropriate API for your target OS.
EDIT
For Windows, a good place to start is here. More specifically, MSDN's CreateFile() is probably a function you would be interested in.