diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..e69de29
diff --git a/lib/dump.asm b/lib/dump.asm
new file mode 100644
index 0000000..5ad8cec
--- /dev/null
+++ b/lib/dump.asm
@@ -0,0 +1,53 @@
+dump:
+  push ax
+  push cx
+  push dx
+  push bx
+  mov al, 0x0A
+  call putc
+  mov al, 0x0D
+  call putc
+  mov cx, 4
+.loop_line:
+  push cx
+  push bx
+  mov ax, bx
+  call print16
+  mov al, ':'
+  call putc
+  mov al, ' '
+  call putc
+  mov cx, 0x8
+.loop_bin:
+  mov ax, [bx]
+  xchg al, ah
+  inc bx
+  inc bx
+  call print16
+  mov dl, ' '
+  call CONOUT
+  loop .loop_bin
+  pop bx
+  mov cx, 0x10
+.loop_ascii:
+  mov dl, '.'
+  cmp byte [bx], 0x20
+  jc .print
+  cmp byte [bx], 0x80
+  jnc .print
+  mov dl, [bx]
+.print:
+  inc bx
+  call CONOUT
+  loop .loop_ascii
+  pop cx
+  mov dl, 0x0A
+  call CONOUT
+  mov dl, 0x0D
+  call CONOUT
+  loop .loop_line
+  pop bx
+  pop dx
+  pop cx
+  pop ax
+  ret
diff --git a/lib/earlymcb.asm b/lib/earlymcb.asm
new file mode 100644
index 0000000..6a12438
--- /dev/null
+++ b/lib/earlymcb.asm
@@ -0,0 +1,65 @@
+%define mcb_first 0x5F
+
+; This alloc uses an MCB-like list always starting at a fixed offset.
+; Boot components may use it to allocate space during early boot.
+; The list ends with the most recently allocated arena at its end,
+; contrary to how the MCBs work on DOS.
+
+; Memory Layout:
+;   0000                 Interrupt table
+;   0400                 BIOS data area
+;   05F0  16 bytes       Arena header 1
+;   0600  BX paragraphs  Arena 1
+;   ....  16 bytes       Arena header 2
+;   ....  BX paragraphs  Arena 2
+;                        ...
+;   ....  16 bytes       Arena header n
+;   ....  BX paragraphs  Arena n
+;                        Unmanaged memory
+
+; Take note that this mechanism works differently than under DOS -
+; but this one is optimized for fast and small alloc.
+
+; Typical usecases:
+; - Diskette Parameter Table (See interrupt 1Eh)
+; - Partition table
+; - Boot sector relocations
+; - Boot sector data (FAT table, rootdir)
+
+; Allocate paragraphs in unmanaged memory
+; IN	BX	requested memory in paragraphs
+; OUT	AX	output segment
+early_alloc:
+  push ds
+  push bx
+  push si
+  ; si is used as zero register
+  ; this allows the opcodes to use a byte as disp instead of word
+  xor si, si
+  mov ax, mcb_first
+.next:
+  mov ds, ax
+  inc ax
+  ; DS is seg of arena header
+  ; AX is seg of arena
+  cmp BYTE [si], 0x4D
+  jne .here
+  add ax, WORD [si+3]
+  jmp .next
+.here:
+  ; mark as item
+  mov BYTE [si], 0x4D
+  ; write segment length in paragraphs
+  mov WORD [si+3], bx
+  ; if allocation is higher than CS, then we are in managed memory
+  ; set ourself as owner then, otherwise use dummy value 8
+  mov bx, cs
+  cmp ax, bx ; CF = CS in unmanaged memory
+  jnc .setup_owner
+  mov bx, 8
+.setup_owner:
+  mov WORD [si+1], bx
+  pop si
+  pop bx
+  pop ds
+  ret
diff --git a/lib/fcbparse.asm b/lib/fcbparse.asm
new file mode 100644
index 0000000..eee48d7
--- /dev/null
+++ b/lib/fcbparse.asm
@@ -0,0 +1,46 @@
+; Parse ASCIIZ string into FCB
+; IN	SI	ptr to filename
+;       BX	ptr to FCB
+fcb_parse:
+  push di
+  push ax
+  mov di, bx
+  xor ax, ax
+  stosb
+.cleanout:
+  push di
+  mov cx, 0x0A
+  mov al, 0x20
+  rep stosb
+  pop di
+.base_loop:
+  call .read
+  cmp al, 0x2E
+  je .ext_start
+  cmp al, 0x20
+  je .ret
+  stosb
+  jmp .base_loop
+.ext_start:
+  mov di, bx
+  add di, 9
+.ext_loop:
+  call .read
+  cmp al, 0x20
+  je .ret
+  stosb
+  jmp .ext_loop
+.read:
+  lodsb
+  test al, al
+  jz .eret
+  cmp al, 0x0D
+  je .eret
+  ret
+.eret:
+  dec si
+  pop ax
+.ret:
+  pop ax
+  pop di
+  ret
diff --git a/lib/fdc.asm b/lib/fdc.asm
new file mode 100644
index 0000000..dbb21e6
--- /dev/null
+++ b/lib/fdc.asm
@@ -0,0 +1,14 @@
+; FDC Descriptor / BIOS parameter block
+fdc_ss:    equ 0x0B ; WORD sector size
+fdc_sc:    equ 0x0D ; BYTE sectors per cluster
+fdc_rsc:   equ 0x0E ; WORD reserved sectors
+fdc_fn:    equ 0x10 ; BYTE FAT tables
+fdc_rde:   equ 0x11 ; WORD root directory entries
+fdc_ts:    equ 0x13 ; WORD total sector count
+                    ;      0 if >65535, use lrgts then
+fdc_mi:    equ 0x15 ; BYTE media descriptor byte
+fdc_sf:    equ 0x16 ; WORD sectors per FAT
+fdc_spt:   equ 0x18 ; WORD sectors per track
+fdc_nos:   equ 0x1A ; WORD sides/heads
+fdc_po:    equ 0x1C ; DWORD partition offset
+fdc_lrgts: equ 0x20 ; DWORD large sector count
diff --git a/lib/log2.asm b/lib/log2.asm
new file mode 100644
index 0000000..b61dbd9
--- /dev/null
+++ b/lib/log2.asm
@@ -0,0 +1,15 @@
+; Calculate dual logarithm (int)
+; IN	AX	number
+; OUT	AX	dual logarithm
+log2:
+  push cx
+  mov cx, 15
+.loop:
+  rcl ax, 1
+  jc .ret
+  loop .loop
+.ret:
+  cmc
+  mov ax, cx
+  pop cx
+  ret
diff --git a/lib/nasmcomp.asm b/lib/nasmcomp.asm
new file mode 100644
index 0000000..4fbebf8
--- /dev/null
+++ b/lib/nasmcomp.asm
@@ -0,0 +1,124 @@
+; Pseudo-Instruction: fill bytes until offset
+%macro pad 1.nolist
+times (%1 - ($-$$)) nop
+%endmacro
+
+; REGISTERS
+%define a al
+%define b ch
+%define c cl
+%define d dh
+%define e dl
+%define h bh
+%define l bl
+%define m byte [bx]
+
+; REGISTER PAIRS
+%define bc cx
+%define de dx
+%define hl bx
+
+; INSTRUCTIONS
+; data movement
+; 'mov' can stay literal
+%define mvi mov
+%define lxi mov
+%macro lda 1
+  mov al, byte [%1]
+%endmacro
+%macro sta 1
+  mov byte [%1], al
+%endmacro
+%macro lhld 1
+  mov bx, word [%1]
+%endmacro
+%macro shld 1
+  mov word [%1], bx
+%endmacro
+%macro ldax 1
+  mov al, byte [%1]
+%endmacro
+%macro stax 1
+  mov byte [%1], al
+%endmacro
+%macro xchg 1
+  xchg dx, bx
+%endmacro
+; addition
+%macro add 1
+  add al, %1
+%endmacro
+%macro adi 1
+  add al, %1
+%endmacro
+%macro adc 1
+  adc al, %1
+%endmacro
+%macro aci 1
+  adc al, %1
+%endmacro
+; subtraction
+%macro sub 1
+  sub al, %1
+%endmacro
+%macro sui 1
+  sub al, %1
+%endmacro
+%macro sbb 1
+  sub al, %1
+%endmacro
+%macro sbi 1
+  sub al, %1
+%endmacro
+; increment / decrement
+%define inr inc
+%define dcr dec
+%define inx inc
+%define dcx dec
+; pointer arithmetic
+%macro dad 1
+  add bx, %1
+%endmacro
+; 'daa' stays literal
+
+;ANA S     10100SSS          ZSCPA   AND register with A
+;ANI #     11100110 db       ZSPCA   AND immediate with A
+;ORA S     10110SSS          ZSPCA   OR  register with A
+;ORI #     11110110          ZSPCA   OR  immediate with A
+;XRA S     10101SSS          ZSPCA   ExclusiveOR register with A
+;XRI #     11101110 db       ZSPCA   ExclusiveOR immediate with A
+
+;CMP S     10111SSS          ZSPCA   Compare register with A
+;CPI #     11111110          ZSPCA   Compare immediate with A
+
+;RLC       00000111          C       Rotate A left
+;RRC       00001111          C       Rotate A right
+;RAL       00010111          C       Rotate A left through carry
+;RAR       00011111          C       Rotate A right through carry
+;CMA       00101111          -       Compliment A
+;CMC       00111111          C       Compliment Carry flag
+;STC       00110111          C       Set Carry flag
+;JMP a     11000011 lb hb    -       Unconditional jump
+;Jccc a    11CCC010 lb hb    -       Conditional jump
+;CALL a    11001101 lb hb    -       Unconditional subroutine call
+;Cccc a    11CCC100 lb hb    -       Conditional subroutine call
+;RET       11001001          -       Unconditional return from subroutine
+;Rccc      11CCC000          -       Conditional return from subroutine
+;RST n     11NNN111          -       Restart (Call n*8)
+;PCHL      11101001          -       Jump to address in H:L
+;PUSH RP   11RP0101 *2       -       Push register pair on the stack
+;POP RP    11RP0001 *2       *2      Pop  register pair from the stack
+;XTHL      11100011          -       Swap H:L with top word on stack
+;SPHL      11111001          -       Set SP to content of H:L
+;IN p      11011011 pa       -       Read input port into A
+;OUT p     11010011 pa       -       Write A to output port
+;EI        11111011          -       Enable interrupts
+;DI        11110011          -       Disable interrupts
+;HLT       01110110          -       Halt processor
+;NOP       00000000          -       No operation
+
+%macro cnz 1
+  jz %%skip
+  call near %1
+%%skip:
+%endmacro
diff --git a/lib/opcode80.asm b/lib/opcode80.asm
new file mode 100644
index 0000000..1334f61
--- /dev/null
+++ b/lib/opcode80.asm
@@ -0,0 +1,142 @@
+; BYTE      name length
+; n BYTES   name
+; BYTE      opcode template (variable parts zero)
+;
+; BYTE      operand 1
+; BYTE      operand 2
+
+; operand types:
+; 0x00      none
+; 0x1n      reg8, opcode |= (reg8 << n)
+; 0x2n      reg16, opcode |= (reg8 << n)
+; 0x3n      reg16b, opcode |= (reg8 << n)
+; 0x7n      3-bit number, opcode |= (num << n)
+; 0x80      imm8, encoded as extra byte
+; 0x81      imm16, encoded as extra word
+
+registers:
+.reg8:
+  db "B", 0
+  db "C", 0
+  db "D", 0
+  db "E", 0
+  db "H", 0
+  db "L", 0
+  db "M", 0
+  db 0
+.reg16:
+  db "BC", 0
+  db "DE", 0
+  db "HL", 0
+  db "SP", 0
+  db 0
+.reg16b:
+  db "BC", 0
+  db "DE", 0
+  db "HL", 0
+  db "AF", 0
+  db 0
+.end:
+  db 0
+
+opcodes:
+  ; Data movement
+  db 3, "MOV",  0b01000000, 0x13, 0x10
+  db 3, "MVI",  0b00000110, 0x13, 0x80
+  db 3, "LXI",  0b00000001, 0x24, 0x81
+  db 3, "LDA",  0b00111010, 0x81, 0x00
+  db 3, "STA",  0b00110010, 0x81, 0x00
+  db 4, "LHLD", 0b00101010, 0x81, 0x00
+  db 4, "SHLD", 0b00100010, 0x81, 0x00
+  db 4, "LDAX", 0b00001010, 0x24, 0x00
+  db 4, "STAX", 0b00000010, 0x24, 0x00
+  db 4, "XCHG", 0b11101011, 0x00, 0x00
+
+  ; Addition / Subtraction
+  db 3, "ADD",  0b10000000, 0x10, 0x00
+  db 3, "ADI",  0b11000110, 0x80, 0x00
+  db 3, "ADC",  0b10001000, 0x10, 0x00
+  db 3, "ACI",  0b11001110, 0x80, 0x00
+  db 3, "SUB",  0b10010000, 0x10, 0x00
+  db 3, "SUI",  0b11010110, 0x80, 0x00
+  db 3, "SBB",  0b10011000, 0x10, 0x00
+  db 3, "SBI",  0b11011110, 0x80, 0x00
+  db 3, "INR",  0b00000100, 0x13, 0x00
+  db 3, "DCR",  0b00000101, 0x13, 0x00
+  db 3, "INX",  0b00000011, 0x24, 0x00
+  db 3, "DCX",  0b00001011, 0x24, 0x00
+  db 3, "DAD",  0b00001001, 0x24, 0x00
+
+  ; BCD
+  db 3, "DAA",  0b00100111, 0x00, 0x00
+
+  ; Bitwise operations
+  db 3, "ANA",  0b10100000, 0x10, 0x00
+  db 3, "ANI",  0b11100110, 0x80, 0x00
+  db 3, "ORA",  0b10110000, 0x10, 0x00
+  db 3, "ORI",  0b11110110, 0x80, 0x00
+  db 3, "XRA",  0b10101000, 0x10, 0x00
+  db 3, "XRI",  0b11101110, 0x80, 0x00
+  db 3, "CMP",  0b10111000, 0x10, 0x00
+  db 3, "CPI",  0b11111110, 0x80, 0x00
+
+  ; Rotate
+  db 3, "RLC",  0b00000111, 0x00, 0x00
+  db 3, "RRC",  0b00001111, 0x00, 0x00
+  db 3, "RAL",  0b00010111, 0x00, 0x00
+  db 3, "RAR",  0b00011111, 0x00, 0x00
+
+  ; Complement
+  db 3, "CMA",  0b00101111, 0x00, 0x00
+  db 3, "CMC",  0b00111111, 0x00, 0x00
+  db 3, "STC",  0b00110111, 0x00, 0x00
+
+  ; Jump
+  db 3, "JMP",  0b11000011, 0x81, 0x00
+  db 3, "JNZ",  0b11000010, 0x81, 0x00
+  db 2, "JZ",   0b11001010, 0x81, 0x00
+  db 3, "JNC",  0b11010010, 0x81, 0x00
+  db 2, "JC",   0b11011010, 0x81, 0x00
+  db 3, "JPO",  0b11100010, 0x81, 0x00
+  db 3, "JPE",  0b11101010, 0x81, 0x00
+  db 2, "JP",   0b11110010, 0x81, 0x00
+  db 2, "JM",   0b11111010, 0x81, 0x00
+
+  ; Call
+  db 4, "CALL", 0b11001101, 0x81, 0x00
+  db 3, "CNZ",  0b11000100, 0x81, 0x00
+  db 2, "CZ",   0b11001100, 0x81, 0x00
+  db 3, "CNC",  0b11010100, 0x81, 0x00
+  db 2, "CC",   0b11011100, 0x81, 0x00
+  db 3, "CPO",  0b11100100, 0x81, 0x00
+  db 3, "CPE",  0b11101100, 0x81, 0x00
+  db 2, "CP",   0b11110100, 0x81, 0x00
+  db 2, "CM",   0b11111100, 0x81, 0x00
+
+  ; Return
+  db 3, "RET",  0b11001001, 0x00, 0x00
+  db 3, "RNZ",  0b11000000, 0x00, 0x00
+  db 2, "RZ",   0b11001000, 0x00, 0x00
+  db 3, "RNC",  0b11010000, 0x00, 0x00
+  db 2, "RC",   0b11011000, 0x00, 0x00
+  db 3, "RPO",  0b11100000, 0x00, 0x00
+  db 3, "RPE",  0b11101000, 0x00, 0x00
+  db 2, "RP",   0b11110000, 0x00, 0x00
+  db 2, "RM",   0b11111000, 0x00, 0x00
+
+  db 3, "RST",  0b11000111, 0x73, 0x00
+  db 4, "PCHL", 0b11101001, 0x00, 0x00
+  db 4, "PUSH", 0b11000101, 0x34, 0x00
+  db 3, "POP",  0b11000001, 0x34, 0x00
+  db 4, "XTHL", 0b11100011, 0x00, 0x00
+  db 4, "SPHL", 0b11111001, 0x00, 0x00
+
+  db 2, "IN",   0b11011011, 0x80, 0x00
+  db 3, "OUT",  0b11010011, 0x80, 0x00
+
+  db 2, "EI",   0b11111011, 0x00, 0x00
+  db 2, "DI",   0b11110011, 0x00, 0x00
+  db 3, "HLT",  0b01110110, 0x00, 0x00
+  db 3, "NOP",  0b00000000, 0x00, 0x00
+
+  db 0
diff --git a/lib/popcnt.asm b/lib/popcnt.asm
new file mode 100644
index 0000000..d03694a
--- /dev/null
+++ b/lib/popcnt.asm
@@ -0,0 +1,30 @@
+popcnt:
+  push bx
+  push cx
+
+  mov bx, ax
+  and ax, 0x5555 ; 8x 01
+  and bx, 0xaaaa ; 8x 10
+  shr bx, 1
+  add ax, bx
+
+  mov bx, ax
+  and ax, 0x3333 ; 4x 0011
+  and bx, 0xcccc ; 4x 1100
+  mov cl, 2
+  shr bx, cl
+  add ax, bx
+
+  mov bx, ax
+  and ax, 0x0f0f ; 2x 00001111
+  and bx, 0xf0f0 ; 2x 11110000
+  mov cl, 4
+  shr bx, cl
+  add ax, bx
+
+  add al, ah
+  xor ah, ah
+
+  pop cx
+  pop bx
+  ret
diff --git a/lib/print.asm b/lib/print.asm
new file mode 100644
index 0000000..582e48d
--- /dev/null
+++ b/lib/print.asm
@@ -0,0 +1,32 @@
+; important functions in this file: kprintf
+
+; print a word
+; in: ax
+print16:
+  xchg ah,al
+  call print8
+  xchg ah,al
+
+; print a byte
+; in: al
+print8:
+  push ax ; avoid destroying ah
+  push bx
+  xor bx, bx
+  aam 16 ; high nibble moved into ah, low nibble into al
+  add ax, 0x3030
+  push ax
+  xchg al, ah
+  call .nib
+  pop ax
+  call .nib
+  pop bx
+  pop ax
+  ret
+.nib:
+  cmp al, 0x3a
+  jl .out
+  add al, 0x07
+.out:
+  call putc
+  ret
diff --git a/lib/printf.asm b/lib/printf.asm
new file mode 100644
index 0000000..9584c70
--- /dev/null
+++ b/lib/printf.asm
@@ -0,0 +1,105 @@
+printf:
+  cld
+  pop si
+  push bp
+  mov bp, sp
+.loop:
+  mov al, [cs:si]
+  inc si
+  cmp al, 0x00
+  je .end
+  cmp al, 0x25
+  je .handle_25h
+.literal:
+  call putc
+  jmp .loop
+.end:
+  pop bp
+  push si
+  ret
+.handle_25h:
+  mov al, [cs:si]
+  inc si
+  cmp al, 0x25
+  je .literal
+  cmp al, 0x58 ; 'X'
+  je .printhex
+  cmp al, 0x55 ; 'U'
+  je .printdec
+  cmp al, 0x53 ; 'S'
+  je .printstr
+  mov al, 0x3F
+  jmp .literal
+.printhex:
+  add bp, 2
+  mov ax, [bp]
+  mov bx, 0x0010
+  call print_number
+  jmp .loop
+.printdec:
+  add bp, 2
+  mov ax, [bp]
+  mov bx, 0x000A
+  call print_number
+  jmp .loop
+.printstr:
+  add bp, 2
+  mov ax, [bp]
+  call print_string
+  jmp .loop
+
+; converts a integer to ascii
+; in    ax      input integer
+;       bx      base
+;	cx	minimum number of digits
+; out   bx      garbled
+;       dx      garbled
+print_number_padded:
+  xor dx, dx
+  div bx
+  push dx
+  dec cx
+  jz .nopad
+  call print_number_padded
+  jmp print_number.end
+.nopad:
+  call print_number
+  jmp print_number.end
+
+; converts a integer to ascii
+; in	ax	input integer
+;	bx	base
+; out	bx	garbled
+;	dx	garbled
+print_number:
+  xor dx, dx
+  div bx ; ax = dx:ax / 10, dx = dx:ax % 10
+  push dx
+  and ax, ax
+  jz .end
+  call print_number
+.end:
+  pop bx
+  xor bh, bh
+  add bx, print_chars
+  mov al, [cs:bx]
+  call putc
+  ret
+
+; putc's a string
+; in	DS:AX	null-terminated string
+print_string:
+  push si
+  mov si, ax
+.loop:
+  lodsb
+  cmp al, 0x00
+  je .end
+  call putc
+  jmp .loop
+.end:
+  pop si
+  ret
+
+print_chars:
+  db "0123456789ABCDEF"
\ No newline at end of file