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    jsandler18
    @jsandler18
    it kinda sucks but oh well
    Zack Penn
    @hikilaka
    ya
    i want to eventually implement a NES emu on this thing
    of course i can do that already with linux, but that's not very fun
    jsandler18
    @jsandler18
    ok_led:
        ldr r0,=0x3F200000 
        mov r1,#1
        lsl r1,#18
        str r1,[r0,#4]
        mov r1,#1
        lsl r1,#16
        str r1,[r0,#40]
    this routine should (maybe) turn on the green led, you can use this as a kind of print statement
    Zack Penn
    @hikilaka
    right, ok cool
    im a little familiar w/ arm assembly so i should be able to write a blink loop
    or hell, not even that
    ill just copy that and see if it turns on for now
    jsandler18
    @jsandler18
    again it might be different for the model 2. play around with it
    Zack Penn
    @hikilaka
    sure.
    jsandler18
    @jsandler18
    if you figure it out, let me know
    Zack Penn
    @hikilaka
    ill let you know
    Zack Penn
    @hikilaka
    aha! i got the ACT led to turn on!
    act_led:
        ldr r0, =0x3f200000
        mov r1, #1
        lsl r1, #21
        str r1, [r0. #16]
        mov r1, #1
        lsl r1, #15
        str r1, [r0, #32]
    so the kernel is being found and executed, i'm guessing somewhere the framebuffer isn't getting initialized properly then
    jsandler18
    @jsandler18
    Hm. My guess is that something in the property interface is being messed up. Try flashing the light on certain return values for the property interface
    jsandler18
    @jsandler18
    Hm. My guess is that something in the property interface is being messed up. Try flashing the light on certain return values for the property interface
    Zack Penn
    @hikilaka
    ya i tried that
    it seems like everything is being initialized correctly
    i've been using the git repo--i may try building a source piece by piece in an attempt to isolate what's going on with it
    jsandler18
    @jsandler18
    Did you assert that the returned framebuffer is nonzero?
    That the pointer you receive is not null?
    Zack Penn
    @hikilaka
    oh--no i didn't
    i'll try later when i get back from class
    benji
    @epicabsol
    could I ask for some help troubleshooting my setup? qemu-system-arm.exe -M raspi2 or any variant thereof crashes on latest qemu, found this bug report for it ( https://bugs.launchpad.net/qemu/+bug/1740887 ), but running the Getting Something to Boot kernel with the old qemu suggested in the bug report does nothing.
    jsandler18
    @jsandler18
    hmm. It seems this is a windows only issue. I would recommend using bash for windows 10. The raspi VM is fairly new and buggy. It is unlikely this issue is going to be fixed on windows any time soon. It would be best to use a linux environment or use real hardware.
    benji
    @epicabsol
    after what seems like ages, I have qemu working on WSL, thanks for that suggestion! For future reference, since WSL doesn't usually have any graphical capabilities, I had to append -nographic -monitor none to the command, but I don't mind running without the qemu window.
    jsandler18
    @jsandler18
    im glad you got it working. unfortunately, no graphics just means you will have to make the jump to real hardware at the framebuffer part instead of at the interrupts part
    benji
    @epicabsol
    Hey, do you have any quick pointers (pun) on how to quickly get reading the SD card?
    Zack Penn
    @hikilaka
    i think you'd have to implement a filesystem
    surely you could find an online implementation tho
    jsandler18
    @jsandler18
    Theoretically, the bootloader should give you some disk access via the ramdisk, but I haven't looked into it.
    Zack Penn
    @hikilaka
    oh right--because it reads the config file, right?
    jsandler18
    @jsandler18
    yeah. Where the ramdisk is initialized is part of the atags. I have not played with it yet, and I have not looked at how you would normally access the sd card
    Zack Penn
    @hikilaka
    i haven't gotten back to trying to get my framebuffer to work btw
    procrastination is my worst enemy
    abhishek1208
    @abhishek1208
    Hey! I just forked the repo and followed all the steps till creating kernel7.img and replaced it in the raspian os boot folder. But i get the rainbow screen! Model - Raspberry pi 3 B
    Are there any pointers for the model 3B?
    jsandler18
    @jsandler18
    I didn't do any work with the model 3, so take what I say about it with a grain of salt, but I found a link that explains how it loads. And different file names to tryhttps://www.raspberrypi.org/forums/viewtopic.php?t=187136
    stewartnjohnston
    @stewartnjohnston
    What version of (hardware) Raspberry Pi is this tutorial for? I can't find this information anywhere in your tutorial.
    jsandler18
    @jsandler18
    I did it with the model 1, but it should work for model 2 and maybe even 3 as well
    Móricz Gergő
    @moriczgergo
    hello!
    any plans to continue the tutorial?
    Móricz Gergő
    @moriczgergo
    also, how did it work with the model 3B at all?
    the final source code w/ locking uses swp which is deprecated in armv8
    Kevin Luty
    @kevlut
    hello, anyone around?
    Chetan Gaonkar
    @ChetanGaonkar1_twitter
    hello
    As suggested in tutorial, I am using qemu version 2.11.0 but on start emulation not showing emulation window. On terminal its saying "VNC Server running on :". Did someone running into same issue?
    Aasrith Chennapragada
    @Aasrith1906
    hey guys , i've been using the tutorial to write an os for a raspberry pi 3 AARCH64 , i converted some of the assembly using different tutorials , it worked fine . but i am having some issues with the framebuffer from the tutorial on qemu , it doesn't work