fixing bootloader again but should work using nasm now

bootloader/boot.asm

@@ -119,20 +119,27 @@ verify_checksum:
 
 lba_to_chs:
     pusha
+
     xor dx, dx
     mov bx, [sectors_per_track]
-    div bx                     ; AX = LBA / sectors_per_track, DX = LBA % spt
-    mov si, ax                 ; temp quotient
+    div bx                     ; AX = LBA / sectors_per_track, DX = remainder (sector number)
+    mov si, ax                 ; SI = temp quotient (track index)
     mov cx, [heads_per_cylinder]
     xor dx, dx
     div cx                     ; AX = cylinder, DX = head
-    mov ch, al                 ; CH = cylinder low
+    mov ch, al                 ; CH = cylinder low byte
     mov dh, dl                 ; DH = head
-    mov cl, sil                ; CL = sector number (0-based)
-    inc cl                     ; Sector is 1-based
-    mov ah, al
-    and ah, 0xC0               ; upper 2 bits of cylinder
-    or cl, ah                  ; insert upper cylinder bits into CL
+
+    ; Now take sector number from earlier remainder
+    mov cx, si                 ; Copy track index to CX to access CL
+    and cl, 0x3F               ; Mask to 6 bits (sector number)
+    inc cl                     ; Sector numbers are 1-based
+
+    ; Insert upper 2 bits of cylinder into CL
+    mov ah, al                 ; AH = cylinder again
+    and ah, 0xC0               ; Get top 2 bits of cylinder
+    or cl, ah                  ; OR them into sector byte
+
     popa
     ret
 

bootloader/boot1.asm

@@ -88,7 +88,7 @@ real_mode_entry:
     inc dword [MemoryMapEntries]
     test ebx, ebx
     jnz .e820_loop
-    jmp .e820_done
+    jmp e820_done
 
 e820_error:
     mov si, e820_error_msg
@@ -112,9 +112,9 @@ vesa_error:
     mov dx, 0x184F         ; Lower-right corner
     int 0x10
 
-    jmp .e820_done         ; Continue booting without VESA graphics
+    jmp e820_done         ; Continue booting without VESA graphics
 
-.e820_done:
+e820_done:
     ; Back to protected mode
     cli
     mov eax, cr0
@@ -123,6 +123,7 @@ vesa_error:
     jmp 0x08:protected_entry
 
 ; ----------------------------------------------------------------
+[BITS 16]
 print_string_16:
 .loop:
     lodsb
@@ -149,8 +150,9 @@ protected_entry:
     rep stosd
     mov edi, page_table
     rep stosd
-
-    mov dword [page_directory], page_table | 0x3
+    mov eax, page_table
+    or eax, 0x3
+    mov [page_directory], eax
     mov ecx, 1024
     mov edi, page_table
     mov eax, 0x00000003
@@ -168,6 +170,13 @@ protected_entry:
 
     jmp kmain
 
+halt:
+    cli
+
+.hang:
+    hlt
+    jmp .hang
+
 ; ----------------------------------------------------------------
 ; Data buffers and variables must be appropriately defined in your data section
 MemoryMapBuffer times 128 db 0          ; 128*24 bytes reserved for E820 memory map (adjust size as needed)
@@ -180,5 +189,15 @@ page_directory times 1024 dd 0
 align 4096
 page_table times 1024 dd 0
 
-times 2047 - ($ - $$) db 0   ; Pad to the second-to-last byte of the 4th sector
-checksum_byte db 0           ; This byte will be calculated and patched later
+%assign pad_size 4096
+%ifdef __SIZE__
+  %define size_current __SIZE__
+%else
+  %define size_current ($ - $$)
+%endif
+
+%if size_current < pad_size
+  times pad_size - size_current db 0
+%endif
+
+checksum_byte db 0