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Working on e820 memory map

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This commit is contained in:
Thomas Oltmann 2025-07-04 16:33:05 +02:00
parent f157f82657
commit 54476eeea1
1 changed files with 22 additions and 0 deletions
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22
lboot.S
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@ -24,6 +24,10 @@ _start: cli
call print
call unreal
mov $msg_memmap, %si
call print
call memmap
mov $msg_fin, %si
call print
1: hlt
@ -67,6 +71,23 @@ unreal: push %ds
2: pop %ds
ret
memmap: push %bp
mov %sp, %bp
sub $24, %sp
mov %ss, %ax
mov %ax, %es
mov %sp, %di
xor %ebx, %ebx
mov $0x534D4150, %edx
mov $24, %ecx
mov $0xE820, %eax
int $0x15
mov %bp, %sp
pop %bp
ret
print: xor %bx, %bx
1: mov $COM1+5, %dx
@ -115,4 +136,5 @@ gdt_ptr: .word gdt_size-1
msg_start: .asciz "Netboot via fernlader v1 ...\r\n"
msg_a20: .asciz " * Enabling A20\r\n"
msg_unreal: .asciz " * Unreal Mode\r\n"
msg_memmap: .asciz " * Fetching Memory Map\r\n"
msg_fin: .asciz "Finished.\r\n"