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You can find better docs at linux-fbdev.org, like the HOWTO. On the mentioned ioctls. In short: they're like INT 10, AH=4F / VESA BIOS calls on an x86 system. There are two structures that hold information about the graphics hardware and its capabilities. -- fix screeninfo. (fb_fix_screeninfo...

levi, #311 - correct. fbio_getvscreeninfo = 0x4600 fbio_putvscreeninfo = 0x4601 fbio_pandisplay = 0x4606 They're ioctl calls defined in fb.h and run by the kernel or the fb kernel module. The screensize can be calculated by multiplying BPP and YRES_VIRTUAL parameters from the virtual...

Hello, I'm happy this thread is alive again. To help you I quickly put together an example that does the following: - framebuffer setup with double buffering - plots 2 pixels on the center of 2nd screen - scrolls the virtual screen from the 480th line to 0 Error checking was removed to shorten...

fbp is the frame buffer pointer. it's the location where the display memory is mapped at. fbfd is framebuffer file descriptor. it's a file handle that points to '/dev/fb0/'.

Here is a short piece of code that draws two pixels on the screen. I added comments and a new macro 'open' that should be added to macro.mac .macro open ffname,ffmode mov r0,pc @ PC points 2 instructions ahead, to the file name b 999f @...

Do not use AND to work with a flag container. AND will clear other bits as well and sets ZERO flag to EQ or NZ if the whole register is 0 or 1. To manipulate/test bit(s) in a word use the following: set: ORR R9,#0b100 @ OR flip: EOR R9,#0b100 @ Exclusive OR, same a XOR on x86 clear...

we can split the code into three parts 1/opening the event devices @ the usual init stuff goes here .title "evlist" .arm .include "macro.mac" ifpandora=1 @ i was writing this code on a zaurus. that's why it's here. .if ifpandora .else key_q=0x10 @ 'q' key scancode for...

Sorry Linux-SWAT, you're going the wrong way. It's not event handling what you're doing in your code. I hope the next code will help you: .title "evlist" .arm .include "macro.mac" evdatalen=0x20 .data evdev: .ascii "/dev/input/event" evnum: .byte 0xff,0 evnamelen=.-evdev-1 .align .text...

I hope this example will help you. To count the digits of a decimal number you have divide the number by 10 (and print out the remainder if you wish) until you get 0. .include "macro.mac" .globl _start printout =1 @ to print out the decimal number reversed count =1 @ to print out...

yes, it does work. i've done it before with some gles code and it worked fine.

you can _start your code in the .data section. here is an example: .include "macro.mac" .globl _start .data _start: print "hello\n" mov r4,#5 1: adr r1,toprintout mov r0,#console mov r2,#2 invoke sys_write ldrb r0,toprintout inc r0 strb r0,toprintout regloop r4,1b exit 0...

I think the ARM procedure call standard assumes you're mixing C (or any other high level code) and ASM code. If you're writing pure ASM code then you don't have to follow this rule. Just preserve what you need. GCC can optimize your register usage when the ASM code is inlined so you don't have...

Levi: >> I'm not familiar with the ! used in dmarshall's 'STMDB sp!,...' though.  That's new syntax to me The "!" means the new SP (after store) is written back to SP. If you leave it out, like STMDB SP,{R4,R5} then SP will point to the same address as before and another call may destroy your...

Here is how LDM/STM works: LDMIA - LDM Increment After LDMDA - LDM Decrement After LDMIB - LDM Increment Before LDMDB - LDM Decrement Before x86 PUSH = ARM STMDB x86 POP = ARM LDMIA To see how segments are allocated under Linux I created a short example.   .include "macro.mac" .globl _start...

printhex: stmdb sp!, {r0-r3,r7,lr} @ save regs mov r2,#7 @ print out 8 numbers sub sp,sp,#8 @ make room for the ascii string on stack 1: and r3,r0,#0xf @ pick the lower nibble 0..f mov r0,r0, ror #4 @ get the next nibble cmp r3,#0xa...

notaz was right. This should be enough for learning the basics. For me, keeping the sources readable is very important. I think following a 'coding style' from the beginning helps to understand and develop the sources for a long time. I still maintain and debug 15 years old x86 assembly codes.

No, you have to alter terminfo settings if you read input events directly. Also, you have to use O_NONBLOCK | O_RD flags when the event device is opened. I have an example somewhere.  I will post it soon.

On Note 1, The code works but try the following: open a file or device, like '/dev/input/event0' and try to read 3 bytes in your example. The first file descriptor on a 'clean' system is 3 so the second loop will read from the event device if more than 3 characters were typed. like this:  ...

Linux-SWAT, As others suggested, why don't you allocate, say 80 bytes and read a full line to the buffer then search for letter 'q'. If it was not typed then print out a message saying something motivating and start it over.   .arm .title "input" .globl _start cmp_char='q' sys_exit=1...

Linux-SWAT: Using syscall 3, sys_read: It returns the character count in R0 so the next loop will read from 1,stdout, not from 0,stdin. Always at least four-align your data. Use an align after a .char declaration OR pack four characters into one .word to save space.