Purple Avenger

[quote=Ancient Dragon;306252]Only two I can think of 1) academic purposes 2) on obscure os that does not have an assembler[/quote] Patches are frequently applied in machine code. NASA's procurement process for Space Shuttle flight software had the vendor providing a "signed off" image. Subsequent fixes after image sign off were …

I'd write an assembler program that just printed out "Hello World" first. In doing that, you'll find you've built 70% of what that date printer does.

We're not going to do your homework for you. Show you made an effort, and then you may get some help.

If you want help, maybe you should ask a question.

Just declare them like any other segment. What their attributes are will be diddled by protected mode code somewhere, not the assembler.

A common fast way to do a multiply by 8 is just shift left by 3 bits.

Almost everything executes faster on the 8086. It has a 16 bit bus rather than the 8088's 8 bit bus. The execution units on the two chips are identical. The only difference is bus width and depth of prefetch queue. The 8088 has a slightly deeper prefetch queue to try …

maybe it wants: "offset message" ? Don't forget that DS needs to be set to the segment the message is in if this code isn't already running with DS=CS

Use DL rather than DX. The group of functions you have to be calling (you didn't say which of several possibilities you're specifying in AH) don't use DH. A MOV to DX is 3 bytes, a MOV to DL is two. Could use '$' terminated string output API too (Int …

Almost all early DOS C compilers can generate hard 87 stuff or emulated 87'. Most assemblers can do it too.

[quote=Ancient Dragon;296247]Since it requires a 100% rewrite of assembly language programs to port from one platform (e.g. 80x88) to another (e.g. AIX Unix), assembly language, by definition, is unportable.[/quote] You can always run the code in an emulator like BOCHS, Hercules, QEMU, etc... A modern x86 CPU can probably emulate …

Sounds like you should be kicked out of school if you waited till the last day to start the assignment. Sympathy is a word in the dictionary.

Hint: index registers

If you use a mutant form of AAM or AAD (I forget which right now) that uses 16 as its base rather than 10, it will cleanly split the nibbles in AL into AH and AL. IOW - 0x35 would become 0x0305

[quote=mathematician;316581]Given that we are told processor belongs to the x86 family...[/quote] The OP never said that. I still can't figure out what they want.

[quote=Metsfan147;316287]are they the only GP registers on a processor[/quote] They are it. [quote=Metsfan147;316287] Also, what's the difference between programmnig for AMD vs Intel and the different chips within these companies.[/quote] No difference, other than errata unless you start wanting to exploit things like 3DNow or MMX/SSE stuff. Stay with the …

[quote=raj140916;311342]Dear friends i am in need of assembly code for interfacing RTC with 8051 microcontroller. plz help me as soon as possible:-|[/quote] It might be more useful to have a hardware design that will work first...since there's probably dozens of different RTC chips and dozens of 8051 variants, and hundreds …

a) What CPU? b) What OS? c) Is this a stock GUI like Windows or X, or a roll your own project where you're doing all the graphics yourself the hard way?

The Space Shuttle's cockpit displays/keypad processors (an IBM SP0) were programmed in assembler as was its Heads Up Display(HUD) symbology processor (Hughs A10INS processor) All of the kernel (and the vast majority of stock drivers and TSR's) for plain old DOS were written in assembler too.

Load an 8 element array of bytes with 0000001B and start rotating them until you find the combination that works. I'll write this program for $1,000. I don't do homework for free.

[quote=shiman999;305474]its really a challenge to write a virus program[/quote] Most I've taken apart with a debugger were written by amateurs and full of bugs, so that's probably a pretty accurate statement.

Whatever that big blog of stuff is, it isn't going to make printable floating point values. I didn't see anything in there doing BCD which almost any reasonable number display routine will have to do.

I would suggest IFDEF'ing out most of that crap and make one small piece work at a time. The "big bang" theory of development and debugging is a very frustrating path to take.

[quote=Mushy-pea;300592]is this proceedure OS specific?[/quote] Always.

If you're guaranteed an NPX, just FILD the values and divide them ;->

What they want you to do is take the CPU's pipeline into consideration when writing the code. On the newer x86 CPU (486 onward) you can get significant speed boosts by ordering stuff so stages of the pipeline don't stall wiating for other stage results. ex. xor cx,cx mov something, …

This is video card/mode dependent. Why graphics mode? If a VESA text mode is available, use that.

The actual hardware RTC lives in the clock chip. Maybe you'd better think about how to retreive stuff out of that before worrying about diaplaying it on the screen. First things first.

[code] ; ; Assuming 386 32 bit assembler code ; mov ecx,val xor eax,eax ; Counts the number of '1' bits again: shl ecx,1 adc eax,0 or ecx,ecx jnz again done: ; ; EAX has the count of bits in "val" ; [/code]