assembly - Writing my own BIOS -


i'm not crazy, reinventing wheel :d
wrote boot-loaders, mouse & keyboard mini-drivers, mini os , on.

i'm trying avoid dos interrupts, using bios ones only, trying go forward unity mini os, decided write own bios :)

the legend said :
high-level programmer, low-level one. 1 day i'll machine-language programmer!

is bios written in assembly? how can flash it? what's mechanism? can start editing current bios?

a bios can written in assembly doesn't have be, parts need to parameters system call since don't match compilers calling convention.

how flash it? varies motherboard motherboard, start open source virtual machine , write bios that. or create virtual machine have written bios. mechanism varies vendor vendor, boot dos (dos not dead, alive in pc world, esp motherboard development , embedded systems). wouldn't mess around real motherboard, if don't know answers of these questions going brick number of motherboards if take path.

you can try take bios upgrade mother board , reverse engineer (although there click through agreement says wont). if figure out can both load , hack @ at. wouldn't go there, brick system before figure out.

is writing bios after? old school, writing 6502 code fun. there many low level problems more useful , interesting.

if can write asm writing machine code not difficult @ all, go fun. x86 dreadful, should spend time learning other systems , asm , machine code (and writing operating systems them). arm dominates world , doesn't rely on bios. have been told video card on non-x86 system still have fiddle in x86 on x86 bios, figure out how bring mainstream video card without need run x86 bios. watch emulator run bios , see does, figure out replace power on init without bios doing it...writing instruction set simulator or disassembler next step beyond writing machine code, wouldn't waste second of time on x86 though, can suggest list of alternatives (or play simulators have written or collected).

if x86 bios way want go, best path write, replace, or hack on bios virtual machine being qemu, virtualbox, or other. replacing bios yours replacing file in directory or using command line option specify alternate bios. once experienced in if there still motherboards legacy bioses on them perhaps can hack way programming 1 (need buy several of each type of motherboard brick some). many embedded systems out there can had $20 $200 same level of experience gained, doesn't make sense hack on pc motherboard without decent schematics , documentation. dig original pc schematic , bios listing being documented, , bios being socketed if yours doesn't boot (and doesn't destroy motherboard) isn't brick can reprogram or replace bios chip. want use microcontroller stand in fake bios, finding right hardware reprogram more bios chips perhaps harder find working original pc's...there amiga community lot more fun , happy have improving/tweaking bios, putting modern hardware behind legacy system calls.


Comments

Post a Comment

Popular posts from this blog

java - Play! framework 2.0: How to display multiple image? -

i need display gallery of photos. here template: @(photos: list[photo]) @title = { <bold>gallery</bold> } @main(title,"photo"){ <ul class="thumbnails"> @for(photo <- photos) { <li class="span3"> <a href="#" class="thumbnail"> <img src="@photo.path" alt=""> </a> </li> } </ul> } and here controller method: public static result getphotos() { return ok(views.html.photo.gallery.render(photo.get())); } and here photo bean : @entity public class photo extends model { @id public long id; @required public string label; public string path; public photo(string path, string label) { this.path = path; this.label = label; } private static finder<long, photo> find = new finder<long, photo>( long.class, photo.class); public static list<phot...
Read more

gmail - Is there any documentation for read-only access to the Google Contacts API? -

i want read-only access user's google contacts. there stackoverflow member wanted this, , received following answer : yes, there is, use https://www.googleapis.com/auth/contacts.readonly scope , "view contacts". this exchange reference read-only access google contacts can find using google. simply using access token obtained attempt read usual google contacts api (i.e. https://www.google.com/m8/feeds ) fails insufficient permissions. similarly, using google contacts api on new target fails 404 errors (for example https://www.googleapis.com/auth/contacts.readonly/default/full ). is there documentation anywhere on how use api, or permissible way access google contacts api full read-write access?
Read more

php - Controller/JToolBar not working in Joomla 2.5 -

relevant code: jtoolbarhelper::custom('savecategories', 'save', '', 'save', false, false); ... <input type="hidden" name="controller" value="easyblogcontroller"> according can dig docs , own previous questions, should call savecategories() function in easyblogcontroller . i've tried setting value easyblog , easyblog.php (file name) current easyblogcontroller (class name). clicking on save button refreshes page. not redirect, echo or var_dump test code put in savecategories() function. var_dump ing jrequest::getvar('controller') , 'task' return correct values. creating controller object , using $controller->execute('task'); works. the values going depend on location of controller trying call, , have couple options here. typically there controller in base folder of component (likely components/com_easyblog) in file called controller.php , class name inside ...
Read more