OSDev.org

Hiya , as some of you may know Ive just completed brans tutorial and have given it my all, I must admit at this point Im just reading about the possibility's and I am getting more enthusiasm the more I read

So Im just bashing through some theory from this page

http://www.osdever.net/tutorials/memory1.php

Its really interesting but now that I have paging setup thanks to brans guide I am unsure of whether to aim to get some kind of memory manager up or whether to start figuring out how to read and write sectors to disk , I figure if I got competant with file handling then if I did run out of memory I could use the HDD/FDD as storage until memory was free. Then again not sure what I would be best doing next so I give myself the best chance while having some fun in the process

Another thing I wanted to mention is that I ordered the indispensable PC hardware book 4th edition , but it will be maybe 2 more weeks in arriving but I was wandering considering I only have £30 now, what is the best book I could get for that price?(£30 = $59.78 at this time)

Books I currently have or will have :

MMURTL developing 32 bit OS
The indispensable PC hardware book

So lets say anyone who reads this post only had those to books and nothing else OSDev related and you had to choose one other with the money constraints I suggested, which book would you buy that would be the absolute most use to you and would teach you as well as be a great referance for OS Dev?

Cheers

I have a few books (university material) that are not OSdev specific, but very useful in that area too. Unfortunately half of it is not in english, the others are like those fat books you can't get for a cheap price.

I have a free book for you though. Kindof dated, but it proved a very interesting read. (and I plug it way too often )
http://www.byte.com/abrash/

Nice Free book

I respect what you are saying about the good books being expensive, I jumped on the PC bandwagon a bit later in life and was actually trying to explain to a family member why Im spending a fair bit on books these days:) , heck in hindsight those dummies books were cheap lol. Im kinda hoping when I get to UNI that I will have access to lots of books, so if yourself or anyone else knows some of the really expensive good books feel free to add. (Hopefully I can raid the uni lol)

Anyway Im just sitting going through the OSDEV theory guides on memory and loading sectors and other things at the moment. I know I'm going to find it hard as hell still but by spending a night on just theory well I think that hobby OS Development without this sites resources would be a nightmare!

Anyway cheers for the link and feedback!

Actually I get

javax.servlet.ServletException: agent.filename property not set in config
file
at com.cmp.nucleus.servlet.NucleusServlet.init(NucleusServlet.java:895)
at com.caucho.server.http.Application.createServlet(Application.java:3114)
at com.caucho.server.http.Application.loadServlet(Application.java:3065)
at com.caucho.server.http.QServletConfig.loadServlet(QServletConfig.java:435)
at com.caucho.server.http.Application.getFilterChainServlet(Application.java:2809)
at com.caucho.server.http.Application.buildFilterChain(Application.java:2765)
at com.caucho.server.http.Invocation.service(Invocation.java:313)
at com.caucho.server.http.RunnerRequest.handleRequest(RunnerRequest.java:346)
at com.caucho.server.http.RunnerRequest.handleConnection(RunnerRequest.java:274)
at com.caucho.server.TcpConnection.run(TcpConnection.java:139)
at java.lang.Thread.run(Thread.java:595)

when I go on that link, maybe its because Im on ubuntu?

I'm on WinXP SP3 and it is doing the same thing regardless of what sublink of the site i go to, even the root page errors.
odd.

I'm on SP2 got the same problem, I also tried just http://www.byte.com/ and got the same error from that...
Jules

I must really have been posting that link too often

Anyway, mirror:
http://public.planetmirror.com/pub/gpbb/
http://www.google.nl/search?client=fire ... gle+zoeken

If that doesn't work, I'lll upload it to my own server.

Hey all

Yeah thats the links working now and one of them has a bunch of PDF files mirrored so looking good Im currently stopping using my usb drive and installed ubuntu on a standard drive as its alot faster + Im building a cross compiler on this faster system then I will have a look at that book as well.

Cheers for checking that out all.

edit: Thats that byte.com site working again for me also now

I'd definatly go for memory manager first, implement something basic (dynamic stack with malloc() and free()) that works without crashing (although may not be performance optimised) so that you can get on with the other aspects of your os.

i need to replace my memory manager, but it will do for now, and i find memory managers hard to write, so i'm putting it off as much as possible.

as for books, if you look online you will be able to find some for >£30, on abebooks.com and amazon, but most of the better ones are around £60 (the indespensible hardware book is £160!)... there is a sticky called book recommendations i advise you to read. you should also look into your local library, i live in a small village outside cambridge and my library was able to order me in books from portsmouth for only £1 each (and they arrived in 6 days), the only draw back is that i can only keep them for 3 weeks, then i have to order them again.

Thanks for your input lukem! , I have actually been busy writing code just to merely turn the LEDS on the keyboard on and off but its just for educational value. Now that I have it working I'm going to start reading about memory management. BTW I now own the indispensable hardware book It arrived 2 days ago, I have only read the first chapter and it was very interesting, its the 4th edition I have , I will need to read more of this book as I don't really know whats all in it as off yet. (Im hopeful that it will come in very handy)

I think in future I'm going to do what you suggest by ordering books via the library as I live relatively close to it! I have looked through the recommendations thread somewhat but I will check the rest out

Just out of curiosity do you have a filesystem in your OS? and are there any docs on the web or even books that you found invaluable when writing your memory manager?

I have spotted a good lot of good guides on OSDev and I'm going to continue reading those though! Its just I now realize that getting and reading as much info sources as possible is key and sometimes I find different people can sometimes yield different results when using google and find something that I may have missed

In regards to that indispensable PC hardware book 4th Edition, heck yeah I paid alot for that and it is in what I would consider well used condition,still the pages are readable and it seems to have diagrams later on showing memory etc, so maybe I will check all that out today, in fact after speaking to you I think I will (I love diagrams , I dunno I kinda feel I understand stuff better when I can accurately visualize whats happening. Its funny thats what one of my tutors always said as well that if you cant picture whats going on you wont manage it(My old programming tutor, hehe he always used to say think in pictures! lol)

I must also admit with the LED code I was messing about with well I wasn't getting anywhere fast until I got a pen and started writing what was happening and working out the results of bitwise AND and ORs on my code.

N.B I may have a look at the OS in your sig at some point if thats okay once I get through the absolute barrage of docs I have to read

yeah, there is a great deal of good information on the internet, although i have to say there is a significant lack of information in certain areas. Another book i'm currently reading is "Operating Systems: Design and Implementation" it is very good, and although im only reading the first edition (the third is most up to date IIRC), it's got a lot of easy to understand theory, and its provoking a lot of design consideration.

there is a fair amount of information on the FAT filesystems available on the wiki, and another good website is osdever.net. you should also look at jamesmolloy.co.uk (very good tutorials, with one on ram filesystems, and one on writing a memory manager), and check out SFS (simple file system).

finally, feel free to look at my OS, the images available on the website are lacking in features, and there is no source currently available, but it might be interesting anyway. I'm currently undecided about open-sourcing my OS, but if i do it won't be until i reach v1.0 anyway (about 6-8 months off), and i still have a bit of GPL code in my source i need to rewrite.

anyway, good luck with your OS

I actually ended up checking how to read and write a sector, but more than anything else at them moment I have been reading multiple articles+ the indispensable hardware book, Im past chapter 6 now+ have made sure I have covered all the theory in the brokenthorn articles as off today so my brain is kinda on information overload

Just for anyone thats interested in the indispensablle hardware book well now that I am getting into the interesting stuff I can 100% say that its an absolute brilliant reference coupled with brans tutorial. What Ive done is jumped between brans guide paging theory+ TI_PC _HW_Book+ brokenthorn paging articles and Im alot happier with paging now .Im kinda unsure how to start my memory management though . I am thinking along the lines of creating a heap then divide the memory up, decide what parts of memory are to get used for what but Im unsure of how to go beyond just slicing memory into blocks to making it so some kind of running task gives out memory to apps.

I am maybe thinking of it all wrong but I am thinking maybe I need to figure out how to have mini programs that run in their own part of virtual memory(e.g each program being its own independent task) before a memory manager is warranted? Its just currently I have memset and memcpy implemented and Im wandering whether to just go on and try and do the multitasking guide thats on osdev(I saw it in the tutorial list but haven't had a chance to read it so not sure how good it is). I have been reading a fair bit about paging and it seems to put alot of things in place(Which Im still digesting all that info hehe) so Im wandering what exactly I can provide by chopping up memory into blocks.

I know a memory manager is needed I actually am unsure of how to go about it though so Im away to see what I can find - its tempting just to use my basic memset, memcpy to set memory and try and get some form of multi-tasking setup. I know little of multi-tasking except that the TSS statement can come into play, I will have to check that out but Im am afraid to because the more I read makes me realize I need to read even 10* more lol

edit-----------------------

Checking out http://www.jamesmolloy.co.uk/tutorial_h ... 0Heap.html and all those guides now, those seem a good continuation of what I was doing and answer some of my dumb assumptions and questions in this latter post hehe

It would be nice to know what books and such some of the article writers had to read before they were able to confidently handle all this stuff(Hopefully in an honest way, not "I read the intel manual once when I was 5 and it all just came to me" , Im just curious to know , Im kinda assuming most of them are computer science students doing Bsc or Msc but still would be good to know for sure and what books really they felt benefited them - I know about the books thread but thats not just specific to the article writers)

To write articles on such a subject in an interesting way which they have achieved in my view must be tricky and to make it understandable. To me that says if they write articles they have a really good grasp of it and must have read some specialist books above and beyond what your average joe reads . I wasn't happy about the high price I paid for the indispensable PC hardware book but now that I have it and Im only at chapter 6 part way through, I realize it is a gem of a book,its already tieing in with some guides.(I'm not sure if it has more code later but Im assuming just well explained theory with minimum code)

Either way looking through

http://www.jamesmolloy.co.uk/tutorial_h ... 0Heap.html

I can see I am going to have to be studying that for a few days minimum. It uses kmalloc which I need to get to grips with all that why its using that, will start on that tomorrow. Also seems to be more stuff for handling paging so I better go through it before I consider writing a memory manager+ it shows how to setup a heap [Seems alot of stuff to consider in this guide though, which is good! but at the same time I think I am going to be reading for months yet lol)

We're using Modern Operating Systems (3rd Ed.) by Andrew S. Tanenbaum as the text for RMIT's Operating System Principles unit. It's interesting. It goes into memory management theory (e.g. paging, segmentation), page replacement algorithms, scheduling algorithms and more from a reasonably high level.

There's little in the way of architecture specific information from a more practical viewpoint, but I'm finding it quite good on the theory side.

I find that there's many textbooks I buy which I use for whatever unit I'm studying that requires it, but I would probably never look at them again in my life. This one, on the other hand, I'll be keeping. Not sure you'll find it for £30 though.