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Ok I fixed it, the updated code is on github. But still in the real hardware hangs forever.MichaelPetch wrote:You don't actually print out an error message if you load a sector successfully
I use RufusMichaelPetch wrote:How do you write your image to the USB stick?
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dd if=disk.img od=x: Yes, where was just a jump to error now is a jump to a specific error with a print:MichaelPetch wrote:Did you add an error message when the 0xaa55 signature wasn't found?
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cmp WORD [0x7DFE], 0xAA55 ; Check Boot Signature
jne error.noBootSignature ; Error if not Boot Signature
...
.noBootSignature:
mov si, Message.Error.NoBootSignature
call BiosPrint
jmp hang
Yes it does not print the error so I think it jumps.MichaelPetch wrote:Did it actually find the disk signature of the VBR?
I used it only for burning ISOs and Floppy images so it could be.MichaelPetch wrote:I don't know anything about RUFUS. Is it writing things as an ISO image?
If "dd" doesn't work for you (it should), give a try to USBImager. Portable executable, no installation required, about 300K only. But it's a GUI app, so unlike "dd" you can't use it from a Makefile.Bonfra wrote:I use RufusMichaelPetch wrote:How do you write your image to the USB stick?
I seriously doubt that. "PhysicalDrive" has nothing to do with volumes, it reflects the raw drive.MichaelPetch wrote:of=\\.\PhysicalDrive1 won't work. It will attempt to access things relative to the volume and not the beginning of the drive.
That works with USBImager perfectly. Tested by many users.MichaelPetch wrote:This was a common problem for people wanting to overwrite the MBR.
I get that (and it is a pretty cool addition to dd on Win). How about "seek" and "skip"? Specially in combination with "PhysicalDrive" (Just a guess)?MichaelPetch wrote:That was the reason Chrysocome DD specifically added the `od=` (and `id=`) options.
Same problem as rufus, the image is written but the bootloader does not work.bzt wrote: give a try to USBImager
Following the guide and cleaning the USB stick, change a bit the result, before it failed instantly, (In the previous screenshot 1M) now it advance to a higher number but still stops at some point.MichaelPetch wrote:You may have to wipe out what is on the USB stick when it comes to existing partitioning info
The code is in ./boot/boot.asm in the github repo. But if works in QEMU and is just a print it should work.MichaelPetch wrote:I almost wonder if you have the right code in the VBR
If this was the case (and has been due to some bugs that I've fixed) it should loop the successful read message since it jumps to itself.MichaelPetch wrote: The only other thing I can think of is that the original bootloader at 0x7c00 was still present and never replaced by the disk read.
He used his own sandisk USB stick and an old compaq but the problem persist, no "Hello, World!" printed. He used rufus.Bonfra wrote:I'm asking a friend to test in his own hardware I'll let you know if it works
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LBA_Packet:
.packet_size db 0x10 ; use_transfer_64 ? 10h : 18h
.reserved db 0x00 ; always zero
.block_cout dw 0x01 ; number of sectors to read
.transfer_buffer dd 0x7C00 ; address to load in ram
.lba_value dq 0x0 ; LBA addres value Code: Select all
align 4
LBA_Packet:
.packet_size db 0x10 ; use_transfer_64 ? 10h : 18h
.reserved db 0x00 ; always zero
.block_cout dw 0x01 ; number of sectors to read
.transfer_buffer dd 0x7C00 ; address to load in ram
.lba_value dq 0x0 ; LBA addres value Sure, just pushed. I've also added the align 4 but nothing changed...MichaelPetch wrote:Take your disk image that you burned and add it to your Github project .
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bits 16
org 0x7c00
jmp short boot
nop
biosParameterBlock:
times 0x52-($-$$) db 0 ; BPB 7.1 FAT32 ends at 0x52.
boot:
mov ax, 0xb800
mov es, ax
mov word [es:0], (0x57 << 8) | 'T'
mov word [es:2], (0x57 << 8) | 'E'
mov word [es:4], (0x57 << 8) | 'S'
mov word [es:6], (0x57 << 8) | 'T'
cli
.hltloop:
hlt
jmp .hltloop
TIMES 510-($-$$) db 0x00
dw 0xaa55