Because my work will get lighter for the next month or so, I decided to mess around with OS's, just to see how they work. I found this website, and I'm trying to run the code he provided. I am following the instructions exactly (to the best of my ability), but when I go to try booting with QEMU, I get this text:
SeaBios (version-blahblah)
Booting from Hard Disk...
Boot failed: could not read the boot disk.
Booting from Floppy...
And it never actually boots. I am relatively new to Ubuntu, and hoping that somebody would be able to point me towards where I made a mistake. I hope this is enough information to diagnose my error, and thanks in advance!
EDIT: Alright, I tried another tutorial which took me through very similar steps (but with slightly different code), and I still had the same issue. I also booted MikeOS from the floppy image it comes with, and it worked fine.
EDIT 2: Aaaaah! I just realized that when I pressed Ctrl+C, the text that was supposed to appear appeared for just a moment, then went away, along with QEMU. What can I do to make the text appear sooner? I've tried moving the infinite loop to after the display command, but to no avail.
I want to start by saying that I didn't read the entire page you provided (as I don't have enough time). However, the error that you cannot boot from HDD, regardless of the OS, usually (always in my previous experiences) means that either the MBA (Master Boot Record) is messed up/incorrect or you don't have a partition with a boot flag on it.
When I have some time I'll look deeper into that page and see if i can find exactly what the problem could be.
Do you have the bytes 0x55, 0xAA at offset 510 of your MBR?
Related
I am working on a non-linear network-optimization problem. When I run a large problem instance on the lab high-performance computers (imposing the time limit of 1 or 2 hours), those computers give me the output when the time is exhausted.
I wanted to use Google Collab to run the same code and to share it with my supervisors (they don't have Pyscipopt installed on their computers). However, when the problem size is small – all is good, but when the problem size is large, it says that the execution is completed (on the bottom of the screen) along with the time it took and a small red exclamation mark BUT it does not show any output for the large-size network optimization problems (neither it prints the solution nor it explains what is the reason/error of this behaviour).
Again, the same code works perfectly fine on high-performance computers, so I do not think there are any problems with syntax.
Please let me know if there are any solutions to the problem described.
Kind regards,
Lidiia
I tried to change "None" in the hardware accelerator to GPU and CPU. I tried to proofread the code in order to find any mistakes. I tried to not leave the Google Collab to run the code at night (I read somewhere that kernel stops working if there is inactivity) so I tried to click on something there to prevent the execution from stopping. Nothing worked.
Getting following exception in my Eclipse '.metadata.log' file that is resulting into almost 80% of CPU usage. Anybody knows what this means? Or how it needs to be fixed? This started after STS plugin was installed on Eclipse.
`
java.util.concurrent.ExecutionException: org.eclipse.lsp4j.jsonrpc.JsonRpcException: java.io.IOException: The pipe is being closed
at java.base/java.util.concurrent.CompletableFuture.reportGet(CompletableFuture.java:396)
at java.base/java.util.concurrent.CompletableFuture.get(CompletableFuture.java:2096)
at org.eclipse.lsp4e.LanguageServerWrapper.lambda$13(LanguageServerWrapper.java:497)
at java.base/java.util.concurrent.CompletableFuture$AsyncRun.run(CompletableFuture.java:1804)
at java.base/java.util.concurrent.CompletableFuture$AsyncRun.exec(CompletableFuture.java:1796)
at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:373)
at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1182)
at java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1655)
at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1622)
at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:165)
Caused by: org.eclipse.lsp4j.jsonrpc.JsonRpcException: java.io.IOException: The pipe is being closed
at org.eclipse.lsp4j.jsonrpc.json.StreamMessageConsumer.consume(StreamMessageConsumer.java:72)
at org.eclipse.lsp4e.LanguageServerWrapper.lambda$3(LanguageServerWrapper.java:265)
at org.eclipse.lsp4j.jsonrpc.RemoteEndpoint.request(RemoteEndpoint.java:161)
at org.eclipse.lsp4j.jsonrpc.services.EndpointProxy.invoke(EndpointProxy.java:91)
at jdk.proxy11/jdk.proxy11.$Proxy35.shutdown(Unknown Source)
at org.eclipse.lsp4e.LanguageServerWrapper.lambda$13(LanguageServerWrapper.java:495)
... 7 more
`
This absolutely is killing my productivity, and I have a very good config machine here, Lenovo t495 with full SSD storage and 32 GB RAM. Just does not make sense. Checked the '.metadata.log' file and just keep seeing this exception.
I think I found the answer. I'm new to Spring, but this is how I resolved it.
Select Spring boot in the setting below.
Also FYI, when I enabled logs in the setting below, I discovered that each of my project source file is being submitted as text to some process, and this is done for each and every file. So, there is entire project text that is being submitted (or something), and 'post' fails, and the plugin proceeds to next file, and these failues happen for each source file. I dont know if the plugin is trying to submit in an 'infinite loop' or something, but that seems to be the case why the CPU usage is spiking and rendering the machine useless.
Enabling 'Spring language server' actually fixed this. I see that there are very momentary spikes of CPU to like 7-10% and nothing more than that after this change.
And then I discover this that, Language server consoles are being created momentarily and then terminated, which explains those little spikes of 7-10% of CPU usage. I really was suffering from this for a month (might sound dumb :|) where my actual tasks were getting delayed, and then this finally fixed it.
I felt that this could have been much more sanely dealt with, not sure if I'm not educated enough to use this plugin given I'm novice in Spring here.
Hope this helps someone!
EDIT:
I think the best way is to just turn this off. After this change, Eclipse still works the same for me, functionally. Hope this plugin works good, and someday will see its benefits.
Long story short, I am tring to run an custom os on REAL hardware. I am using http://www.brokenthorn.com/Resources/OSDevIndex.html this tutorial as guild line(more like copy 99% of there code there). I made it to page 20 there (demo15) and there i got into a problem, its explained there how to read from a flopy, and I have a hard drive in the laptop! so i started working on a ahci and pci driver and it was going pretty well. But then somthing wired happend I discoved that when the kernel size is more than 17kb is doesnt work. I have no idea to why and i have been stuck on it for 5 days now working on it every day. I know its the size that matter and not the code through my experiments with it. But it runs ok in Bochs only not on read hardwear.
Everything works as long as the kernel is less than 17kb and if its not than when its jump to the kernel entry point is stops or start a infinit loop where it restarts itself for some reason. Well wasnt very short story in the end sorry.
Anyway It will be realy helpful if someone has any idea to why its like that or how to fix it.
I know you dont have my laptop so you cant realy test anything but even an idea to why will help my.
my code is on github https://github.com/xXvilckoXx/os, here.
I am working on VS C++ 2010 express.
Sorry for my bad english and thank to everyone who takes his time to try help me or even just reading this post!
I recently had a frustrating problem:
Modbus-connection throws in bError 4 as soon as bExecute is turned on. No variables could be read, and error persisted until reboot.
Previously working project stopped working over the weekend.
I might have fiddled around inside PLC, uninstalling couple libraries mainly, but logically thinking nothing should be wrong and I didnt do much at all. Its still possible I done goofed on friday, and didnt notice until after weekend.
On to the troubleshooting:
Reboot both machines
State machine is fine. Even made stripped-down project with one input and output and previously working minimalist state machine.
Reinstalled Modbus library in PC and PLC
Git revert the code couple weeks to a time when I 100% knew it worked.
PLC can ping PC in 1ms
Had an old project zipped in store, including "original" libraries
Reboot again
I still could wipe out PLC OS and start anew, but lets save that off for now.
"Thats all a mere mortal can do." I thought, and shot off a mail to Beckhoff.
Lets shoot off a mail to Beckhoff support.
Troubleshooting ensues:
Strip down the program even further, so only FB_MBReadInputs stays and bExecute can be flipped on or off manually.
Running only MBReadInputs, only MBWriteCoils, both at the same time
bError 4 problem persists no matter how much is stripped or ran.
Running the same project Locally on PC works just fine. Inputs can be read and output bits can be written.
In the end, flashing new image ended up being the solution.
Still in process of fiddling that out, so the actual problem isnt yet solved.
Update: Stuff works as it should. Some cosmic ray must have hit SD-card just right so during the weekend things got awry and problems surfaced.
Beckhoff image repo in my case: https://download.beckhoff.com/download/software/embPC-Control/CX90xx/CX9020/CE/TC3
Thats it, in the end wiping out SD-card is pretty basic thing to do when facing larger problems, but I just wanted to go through all the troubleshooting steps and end results for anyone struggling with Modbus and Twincat as much as I have.
I just reached out the same problem on CX8180. In my case there was some program uploaded before mine. I've activate my configuration and run PLC - get bError 4. TwinCAT errors code list says that is something with ADS mailbox and too much ADS calls. My program works fine on the same hardware elsewhere. Restart origin and activate configuration doesn't work.
I need to login with CeRHost and make a reboot of PLC. After that move communication works like a charm. The problem was the previous modbus communication.
I don't know if this is allowed here but can someone help me why am I getting this random blue screen? It say's whea uncorrectable error but I don't know which part of my PC is faulty. I noticed the BSOD appears when there is a heavy task like when I am coding in VSCode (running npm install, etc). I will attach here the minidump if someone can read it. If you need more information about my PC, let me know. Please I really need your help. I want to use this PC for programming. Thanks!
Latest Minidump File
This usually happens due to the high temperature in your pc, driver related issues or corrupted hardware. I recommend you try stopping overclocking for some time (if it is) and check if the problem persists. If not, then I think there could be a problem with your hardware itself. Try replacing the motherboard.