I'm looking for a small (<16MB on flash) open source os, preferrably a linux distribution to run on a Cavium Octeon SoC (MIPS64). Hardware also limits me to either run from memory (and preferrably be able to install from there) or use a network installer. Bootloader for the system in question is u-boot and I find it unlikely that it would be wise to attempt to change it.
The only thing I've found that's even close is a limited functionality tor ramdisk (torramdisk) from a few years back, but looks like installation is going to be tough.
I'm trying to not rebuild the wheel here, thanks for your time.
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I'm getting started with freeRTOS. I went through the documentation provided in freeRTOS.org, and had some practice with some demo projects. My question is how to install freeRTOS without using the win32 port (since it is only an emulator that doesn't provide real time behaviour)? Is it possible to install freeRTOS as a standalone OS, or is it necessary to use linux kernel or windows?
FreeRTOS is a real time operating system kernel. It's not a fully blown OS, it's just the kernel. You don't "install" FreeRTOS like you would windows or a ubuntu distro on an x86 PC. You build a project and use freeRTOS to schedule tasks, manage memory resources etc. In general, you need a different microcontroller/processor than one you're developing on as your platform.
If you want to use only your laptop, then you'll need to simulate a "target" processor (that's what that option is). You won't be able to achieve "real time" results (windows will get in the way), but you can get pretty close.
The first thing I'd do is get an eval kit for whatever microcontroller you want to actually use/target/develop on.
Im developing an uwp app on Raspberry Pi 3 with Windows IOT Core. But after I deploy my app and use it for couple days the os crashes. It says something went wrong. It says "Your pc ran into a problem and needs to restart". It restarts couple times but still same error on every boot.
I tried to remove the sd card(Class 10,64 GB) format it and reinstall everything. At first it was okay but after some time same error appears.
I tried to use different os builds and it didnt work.
I tried to use industrial power supply (5V3A) and also it didnt work.
My SD Card is not one of the recommended ones but do I really have to get the recommended sd cards to use the windows iot core properly?
"Your PC ran into a problem and needs to restart" is a typical blue screen message seen on Windows systems from the last few years - laptops and desktops with far larger hard drives and no SD card. The error is not associated with a RAM or disk space shortage (operating systems running in graphical mode usually monitor and actively warn about either). In your case, it is showing at startup, when not much is running (taking up RAM), and you can check the amount of space used on the card with the PC.
The key stats for SD cards are size (you have plenty) and speed (clearly enough or you would have trouble installing/running anything after starting the Pi). The cause is something else, and finding out what will require getting a more detailed error message from Windows - "a problem" could mean anything. In my experience, blue screen errors have mostly involved having a wrong driver installed, sometimes a bad Windows update - but IoT Core has its own alternatives, like "bad system configuration". Look for the underscored string (e.g., BAD_SYSTEM_CONFIG_INFO) at the end of your blue screen message, as that is the first hint.
Unfortunately, most Windows BSoD documentation is for traditional PCs, so I cannot recommend specific troubleshooting tools and be sure that they will run on the Pi.
You can use Windows Debugger to debug the kernel and drivers on Windows IoT Core. WinDbg is a very powerful debugger that most Windows developers are familiar with. Or you can also refer to this topic in MSDN, it shows how to create the dump file when the app crashes. If possible, you can share your code so that we can reproduce the issue.
Since our application grows, we need more space on our Windows CE devices.
If I install CF app in RAM on win ce device this app vanished after cold restart.
I have used the simplest choice install on flash card. As I mentioned running applications from the sd card is slow and there are some heavy issues with demand-paging if you run the apps from persistent paths. Isn't it? Is it worth to install it there? Will we get performance problems?
Should I use another solution - install after cold restart/new start on RAM from flash disk (if it possible)? Where can/should I store settings/log files? On flash/sd card?
There's no "one size fits all" answer for this.
If you move the app from memory to storage you'll gain RAM. Maybe that boost in RAM will give the EE more heap space and thereby prevent GC thrashing. That would give you better perceived performance. But maybe it won't and it will just increase demand-paging for your app and hurt performance. Maybe you'll get a little of both and it's a wash.
How would you handle persistence to RAM? That depends on what your device supports for auto-running apps.
Where should you store settings and logs? Again, that depends on the device, the storage, the size, the frequency of access and loads of other things.
Basically the answer for all of these is only going to be found by you testing your actual app on your actual hardware. Try the difference scenarios and collect metrics to see which performs better. That's the only "correct" answer.
I am aware that there are programs out there like lojack for laptops that get installed on the BIOS, but I'm still a little confused. When reading about lojack, it seems to me that they can't fully located the laptop's location until the user logs in and tries to access the internet. So I'm thinking that it's a BIOS application so that it wouldn't matter if the thief reformats the HD.
So my question is, does anyone have any ideas of how an internet enables BIOS application would be written. I'm not looking for full answers -- just ideas or resources to get started. For example, is such a thing written in assembly? Once one such app is written, how does it get transfered to the BIOS.
Does the BIOS program itself recognize that there is an internet connection (when the thief logs on to the OS). Or upon logon, does additional processes get spawned? Are there any resources/websites that anyone can direct me too?
You didn't mention whether you were interested in legacy BIOS or EFI BIOS, but I would mention that with EFI there is the capability of writing EFI applications. See Intel Press:
Harnessing the UEFI Shell
The EFI Application toolkit comes with a complete TCP/IP network stack:
http://www.intel.com/technology/efi/toolkit_overview.htm
More at tianocore.org
Regarding "LoJack"-style solutions, one of the providers of this technology is Absolute Software's Computrace product.
Basically there are 3 components: 1) a software component that runs in the OS; 2) a BIOS component which is baked into the system BIOS (accomplished via Absolute working with the PC vendor); 3) servers at Absolute software that talk to the PC.
For more information on how it works visit:
http://www.absolute.com/en/company/Computrace-Persistence.aspx
(see especially the demo video on this site)
To learn something about BIOS, one good source is coreboot.org. It is an open source BIOS (or firmware) and support some physical machines.
Legacy BIOS is written in assembly language, but new generations, such as UEFI or coreboot, are written mostly in C language. BIOS program is stored in the ROM, and executed by the CPU automatically.
The BIOS program itself does not access the internet or perform any of the advertised functions. The LoJack addition to the BIOS firmware is a file copying/patching utility - at boot up it can check the harddrive for a copy of Windows and proceed to silently install/repair the LoJack service if it has been removed. The service itself includes several measures to lower it's profile and prevent itself from being disabled (similar to how many trojans and malware run several processes that each restore the other if one is disabled or killed).
The LoJack BIOS program can't do anything if a unsupported operating system (like Linux) is installed after the harddrive is wiped.
I've just installed pfSense (a FreeBSD distro) and I'm having problems with my Ethernet adapters - I seem to be able to get it into a state where I cannot ping any machine despite the ARP tables etc... all being correct (On the machine I'm pinging I can see the packets arrive and the response sent in Wireshark, but the remote machine gets nothing)
Having an interest and limited knowedge in OS development I kind of want to have a go at debugging this, but in many ways I'm not really sure where to start:
How do I go about getting the source code for the drivers I'm using? Will they be part of the FreeBSD source code, or is there going to be some external project? (or are the drivers I'm using likely to be the proprietry ones released by Realtek, and therefor not have source code)
For that matter, how do I identify what drivers I'm currently using?
Finally, are there any good resources on how to debug Kernel-level / device drivers?
(I appologise if I'm asking silly questions or if I seem overly optimistic about what I'm hoping to achieve by debugging this, but although I lack experience in this area I consider myself to be a smart guy and I've gotta start somewhere!)
I really doubt your problem is in the device drivers or other kernel code. Check the PF rules - you most probably just dropping all ICMP packets out right.