diff --git a/.gitignore b/.gitignore
index dee4724..d8a12b1 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,8 @@
+*.com
+*.bs
+*.0
+*.lst
+*.img
 *.bin
-scripts/
+*.rom
+/scripts
diff --git a/Makefile b/Makefile
index 31dda32..d1b30a8 100644
--- a/Makefile
+++ b/Makefile
@@ -1,17 +1,81 @@
-.PHONY: default
+FLOPPY = 360
 
-cp437.bin: src/cp437.bmp scripts/bmp2font
-	scripts/bmp2font $< $@
+PROGRAMS = $(patsubst %.asm,%.com,$(wildcard com/*.asm))
+DISTFILES = $(PROGRAMS)
+ROMS =
 
-vga11.bin: src/vga11.asm cp437.bin
-	nasm -o $@ $<
+QEMU_ARCH = $(shell uname -m)
+QEMU = qemu-system-$(QEMU_ARCH)
+QEMU_ARGS = $(addprefix --option-rom ,$(ROMS))
 
-forth.bin: src/forth.asm
-	nasm -o $@ $<
+NASM = nasm
+NASM_ARGS = -s -Ilib -Plib/nasmcomp.asm -w-macro-params
 
-scripts/%: src/scripts/%.c
-	mkdir -p scripts
-	gcc -o $@ $<
+EMUL = utils/emul
+
+ifdef KVM
+QEMU_ARGS += --enable-kvm
+endif
+
+ifdef DEBUG
+ROMS += rom/debug.rom
+NASM_ARGS += -l $(basename $@).lst
+endif
+
+ifndef DISPLAY
+QEMU_ARGS += --display curses
+endif
+
+.PHONY: default bootstrap clean qemu-rom qemu-floppy qemu-pxe
+
+default: fdimage.img
+
+# Host utils
+utils/%: src/utils/%.c
+	mkdir -p utils
+	$(CC) -o $@ $<
+
+cp437.bin: src/cp437.bmp utils/bmp2font
+	utils/bmp2font $< $@
+
+# BIOS option roms
+rom/%.rom: rom/%.asm utils/fix-rom
+	$(NASM) $(NASM_ARGS) -o $@ $< && utils/fix-rom $@
+
+# COM programs
+%.com: %.asm
+	$(NASM) $(NASM_ARGS) -DCOM -DBASE=0x0100 -o $@ $<
+
+# Bootloaders, first sector on partition
+%.bs: %.asm
+	$(NASM) $(NASM_ARGS) -DBOOT -DBASE=0x7C00 -o $@ $<
+	: check boot signature
+	test "$$(echo $$(xxd -p -l 2 -s 510 pxe.bs))" == 55aa
+
+# Network bootstrap protocol as used for PXE
+%.0: %.asm
+	$(NASM) $(NASM_ARGS) -DNBP -DBASE=0x7C00 -o $@ $<
+
+fdimage.img: boot/fat.bs $(BDOSIMG) $(BIOSIMG) $(DISTFILES)
+	mformat -R 9 -C -i $@ -f $(FLOPPY) -B boot/fat.bs ::
+	dd if=$(BDOSIMG) bs=512 seek=1 count=4 conv=notrunc of=$@
+	dd if=$(BIOSIMG) bs=512 seek=5 count=4 conv=notrunc of=$@
+	mcopy -i $@ $(DISTFILES) ::
+
+hdimage.img: boot/mbr.bs fdimage.img
+	cat boot/mbr.bs fdimage.img >$@
 
 clean:
-	rm -f *.bin scripts/*
+	rm -f *.com *.bs *.0 *.lst *.img *.bin *.rom
+
+qemu-floppy: fdimage.img $(ROMS)
+	$(QEMU) $(QEMU_ARGS) -boot a -fda fdimage.img
+
+qemu-hdd: hdimage.img $(ROMS)
+	$(QEMU) $(QEMU_ARGS) -boot c -hda hdimage.img
+
+qemu-pxe: pxe.bs $(ROMS)
+	$(QEMU) $(QEMU_ARGS) -boot n \
+		-option-rom /usr/share/qemu/pxe-rtl8139.rom \
+		-device e1000,netdev=mynet0,mac=52:54:00:12:34:56 \
+		-netdev user,id=mynet0,net=192.168.76.0/24,dhcpstart=192.168.76.9,tftp=$(CURDIR),bootfile=pxe.bs
diff --git a/bdos/8086.asm b/bdos/8086.asm
deleted file mode 100644
index 1d7fd46..0000000
--- a/bdos/8086.asm
+++ /dev/null
@@ -1,234 +0,0 @@
-ORG BDOS
-
-%include "hdr/bios.asm"
-%include "hdr/fcb.asm"
-%include "hdr/bpb.asm"
-
-DISKBUF: EQU (BDOS-0x200) ; deblocking
-DISKBPB: EQU (DISKBUF-21) ; BPB of the current driv
-DISKDRV: EQU (DISKBPB-1) ; BYTE denoting drive of current fcb (1=A, ...)
-
-PROGBX:  EQU (DISKDRV-2)
-
-STACK:   EQU (PROGBX & 0xFFFE) ; even address, grows down
-
-DEFDRV:  EQU 4 ; default drive when opening a FCB (1=A, ...)
-
-SYSCALL:
-  MOV [PROGBX], BX
-  XOR BH, BH
-  MOV BL, CL
-  ADD BX, BX
-  ADD BX, FUNCS
-  MOV BX, [BX]
-  PUSH BX
-  MOV BX, [PROGBX]
-SYSRET:
-  RET
-
-FUNCS:
-DW SETUP,GETC,PUTC,SYSRET
-DW SYSRET,SYSRET,SYSRET,SYSRET
-DW SYSRET,PUTS,GETS,STATUS
-DW SYSRET,DISKRST,SETDEFDSK,FCBOPEN
-DW SYSRET,SYSRET,SYSRET,SYSRET
-DW SYSRET,SYSRET,SYSRET,SYSRET
-
-SETUP:
-  MOV SP, STACK
-  MOV BYTE [DEFDRV], 0x01
-  MOV CX, DISKBUF
-  CALL SETDMA
-
-  SUB SP, 0x20
-  MOV BX, SP
-  CALL FCBOPEN
-
-  CLI
-HALT:
-  HLT
-  JMP HALT
-
-GETC:
-  CALL CONIN
-  TEST AL, AL
-  JZ GETC
-  PUSH DX
-  MOV DL, AL
-  CALL CONOUT
-  POP DX
-  ret
-
-PUTC:
-  JMP CONOUT
-
-PUTS:
-  PUSH SI
-  MOV SI, DX
-PUTS_L:
-  MOV DL, BYTE [SI]
-  CMP DL, '$'
-  JZ PUTS_E
-  CALL CONOUT
-  INC SI
-  JMP PUTS_L
-PUTS_E:
-  POP SI
-  RET
-
-; BX base ptr to buffer
-; CH maximum BL
-; CL minimum BL
-GETS:
-  PUSH AX
-  PUSH CX
-  PUSH DX
-  PUSH BX
-  ; BX is base pointer
-  MOV BX, DX
-  ; CL is maximum, CH is current position
-  MOV CX, [BX]
-  XOR CH, CH
-  ; BX starts at actual character area
-  ADD BX, 2
-GETS_L:
-  ; Read and maybe handle control chars
-  CALL GETC
-  CMP AL, 0x0D
-  JE GETS_E
-  CMP AL, 8
-  JE GETS_BS
-  ; Store character
-  PUSH BX
-  ADD BL, CH
-  ADC BH, 0
-  MOV [BX], AL
-  POP BX
-  ; Loop if we arent full yet
-  INC CH
-  CMP CH, CL
-  JC GETS_L
-GETS_E:
-  ; Append LF to CR
-  MOV DL, 0x0A
-  CALL PUTC
-  ; Write back length data
-  SUB BX, 2
-  MOV [BX], CX
-  ; Restore registers
-  POP BX
-  POP DX
-  POP CX
-  POP AX
-  ret
-GETS_BS:
-  TEST CH, CH
-  JZ GETS_L
-  MOV DL, 0x20
-  CALL PUTC
-  MOV DL, 8
-  CALL PUTC
-  DEC CL
-  JMP GETS_L
-
-STATUS:
-  JMP CONST
-
-DISKRST:
-  MOV BYTE [DISKDRV], 0xFF
-  RET
-
-SETDEFDSK:
-  MOV BYTE [DEFDRV], DL
-  RET
-
-FCBOPEN:
-  MOV CL, BYTE [BX]
-  TEST CL, CL
-  JNZ NODEFDRV
-  MOV CL, BYTE [DEFDRV]
-  MOV BYTE [BX], CL
-NODEFDRV:
-  CALL LOADBPB
-
-  MOV CX, [DISKBPB+BPB_RDE]
-
-  CALL FATSIZE
-  ADD DX, WORD [DISKBPB+BPB_RSC]
-  CALL SETLSEC
-  CALL READ
-
-  MOV AX, [DISKBUF]
-
-  INT3
-  ; TODO: search for file in rootdir
-  ; TODO: init cluster number
-  RET
-
-; Set logical sector number
-; IN DX sector number
-SETLSEC:
-  PUSH AX
-  PUSH CX
-  PUSH DX
-  XOR AX, AX
-  XCHG AX, DX
-  DIV WORD [DISKBPB+BPB_SPT]
-  MOV CX, AX
-  CALL SETTRK
-  MOV CX, DX
-  INC CX
-  CALL SETSEC
-  POP DX
-  POP CX
-  POP AX
-  RET
-
-; OUT DX number of sectors by all FATs
-FATSIZE:
-  PUSH AX
-  MOV DL, BYTE [DISKBPB+BPB_FN]
-  MOV AL, BYTE [DISKBPB+BPB_SF]
-  MUL DL
-  XCHG AX, DX
-  POP AX
-RET:
-  RET
-
-; IN CL drive num, 1=A, 2=B, 3=C
-LOADBPB:
-  CMP BYTE [DISKDRV], CL
-  JE RET
-
-  PUSH CX
-  DEC CL
-  CALL SELDSK
-  ; first track
-  MOV CX, 0
-  CALL SETTRK
-  ; first sector
-  MOV CX, 1
-  CALL SETSEC
-  ; into default diskbuf
-  MOV CX, DISKBUF
-  CALL SETDMA
-  POP CX
-
-  CALL READ
-  JC DISKRST
-
-  ; copy BPB
-  PUSH CX
-  PUSH SI
-  PUSH DI
-  MOV CX, 21
-  MOV SI, DISKBUF+0x0B
-  MOV DI, DISKBPB
-  REP MOVSB
-  POP DI
-  POP SI
-  POP CX
-
-  ; store drive number
-  MOV BYTE [DISKDRV], CL
-  RET
diff --git a/bios/8086.asm b/bios/8086.asm
deleted file mode 100644
index 594dff9..0000000
--- a/bios/8086.asm
+++ /dev/null
@@ -1,218 +0,0 @@
-ORG BIOS
-CPU 8086
-
-DISKCX: EQU 0x8
-DISKDX: EQU 0xA
-DISKBX: EQU 0xC
-
-JMP NEAR BOOT
-JMP NEAR WBOOT
-JMP NEAR CONST
-JMP NEAR CONIN
-JMP NEAR CONOUT
-JMP NEAR LIST
-JMP NEAR PUNCH
-JMP NEAR READER
-JMP NEAR HOME
-JMP NEAR SELDSK
-JMP NEAR SETTRK
-JMP NEAR SETSEC
-JMP NEAR SETDMA
-JMP NEAR READ
-JMP NEAR WRITE
-JMP NEAR LISTST
-
-BOOT:
-  MOV AL, 0x86
-  CALL MSG
-  DB "BIOS", 0
-
-WBOOT:
-  XOR CX, CX
-  JMP BDOS
-  RET
-
-; CHAR I/O
-CONST:
-  MOV AH, 1
-  INT 0x16
-  JZ .END
-  MOV AL, 0xFF
-  RET
-.END:
-  XOR AL, AL
-  RET
-
-CONIN:
-  XOR AX, AX
-  INT 0x16
-  TEST AL, AL
-  JZ CONIN
-  RET
-
-MSG:
-  POP SI
-.LOOP:
-  MOV DL, BYTE [SI]
-  INC SI
-  TEST DL, DL
-  JZ .END
-  CALL CONOUT
-  JMP .LOOP
-.END:
-  MOV DL, 0x20
-  CALL CONOUT
-  CALL PRINTAL
-  MOV DL, 0x0A
-  CALL CONOUT
-  MOV DL, 0x0D
-  CALL CONOUT
-  PUSH SI
-  RET
-
-PRINTAL:
-  PUSH AX
-  PUSH DX
-  AAM 16
-  MOV DL, AH
-  CALL PRINTNIB
-  MOV DL, AL
-  CALL PRINTNIB
-  POP DX
-  POP AX
-  RET
-
-PRINTNIB:
-  ADD DL, 0x30
-  CMP DL, 0x3a
-  JL CONOUT
-  ADD DL, 0x07
-
-CONOUT:
-  PUSH AX
-  PUSH BX
-  MOV AH, 0x0E
-  MOV AL, DL
-  XOR BX, BX
-  INT 0x10
-  POP BX
-  POP AX
-  RET
-
-LIST:
-  PUSH DX
-  XOR AH, AH
-  MOV AL, DL
-  INT 0x17
-  POP DX
-  RET
-
-LISTST:
-  STC
-  RET
-
-PUNCH:
-  STC
-  RET
-
-READER:
-  STC
-  RET
-
-; DISK I/O
-HOME:
-  MOV WORD [DISKCX], 0x0001
-  MOV BYTE [DISKDX+1], 0x00
-  RET
-
-SELDSK:
-  MOV BYTE [DISKDX], CL
-  XOR BX, BX
-  RET
-
-SETTRK:
-  PUSH CX
-  PUSH DX
-
-  MOV DX, CX
-  ; CH for headnum, CL for SAL
-  MOV CX, 0x0006
-
-  ; Take off LSB as head number
-  XOR CH, CH
-  RCR DX, 1
-  RCL CH, 1
-  MOV BYTE [DISKDX+1], CH
-
-  ; DX is sector number now
-  ; Shift into format for int13
-  ; DX ------9876543210
-  SAL DX, CL
-  ; DX 9876543210------
-  ROL DX, 1
-  ROL DX, 1
-  ; DX 76543210------98
-  SAL DL, CL
-  ; DX 7654321098------
-  AND WORD [DISKCX], 0x003F
-  OR WORD [DISKCX], DX
-
-  POP DX
-  POP CX
-  RET
-
-SETSEC:
-  AND WORD [DISKCX], 0xFFC0
-  OR BYTE [DISKCX], CL
-  RET
-
-SETDMA:
-  MOV WORD [DISKBX], CX
-  RET
-
-READ:
-  PUSH CX
-  PUSH DX
-  PUSH BX
-
-  MOV AX, 0x0201
-  MOV CX, [DISKCX]
-  MOV DX, [DISKDX]
-  MOV BX, [DISKBX]
-  INT 0x13
-  XCHG AH, AL
-
-  POP BX
-  POP DX
-  POP CX
-
-  JC DISKERR
-  RET
-
-WRITE:
-  PUSH CX
-  PUSH DX
-  PUSH BX
-
-  MOV AX, 0x0301
-  MOV CX, [DISKCX]
-  MOV DX, [DISKDX]
-  MOV BX, [DISKBX]
-  INT 0x13
-  XCHG AH, AL
-
-  POP BX
-  POP DX
-  POP CX
-
-  JC DISKERR
-  RET
-
-DISKERR:
-  PUSHF
-  PUSH SI
-  CALL MSG
-  DB "DISKERR", 0
-  POP SI
-  POPF
-  RET
diff --git a/src/scripts/bmp2font.c b/bmp2font.c
similarity index 100%
rename from src/scripts/bmp2font.c
rename to bmp2font.c
diff --git a/com/asm86.asm b/com/asm86.asm
deleted file mode 100644
index cfb0da9..0000000
--- a/com/asm86.asm
+++ /dev/null
@@ -1,21 +0,0 @@
-org 0x100
-
-jmp start
-
-%include "fcbparse.asm"
-
-fcb_asm:
-  times 36 db 0
-
-fcb_bin:
-  times 36 db 0
-
-fcb_lst:
-  times 36 db 0
-
-start:
-  mov si, 0x81
-  mov bx, fcb_asm
-  mov ax, 0x1234
-  call fcb_parse
-  ret
diff --git a/com/hello.asm b/com/hello.asm
deleted file mode 100644
index ff02195..0000000
--- a/com/hello.asm
+++ /dev/null
@@ -1,17 +0,0 @@
-org 0x0100
-
-main:
-  mov si, hello
-.loop:
-  lodsb
-  test al, al
-  jz .ret
-  mov dl, al
-  mov cl, 0x02
-  call 5
-  jmp .loop
-.ret:
-  ret
-
-hello:
-  db "Hello!", 0x0A, 0x0D, 0
diff --git a/src/cp437.bmp b/cp437.bmp
similarity index 100%
rename from src/cp437.bmp
rename to cp437.bmp
diff --git a/boot/fat.asm b/fat.asm
similarity index 100%
rename from boot/fat.asm
rename to fat.asm
diff --git a/src/utils/fix-rom.c b/fix-rom.c
similarity index 100%
rename from src/utils/fix-rom.c
rename to fix-rom.c
diff --git a/hdr/bios.asm b/hdr/bios.asm
deleted file mode 100644
index 9a645b0..0000000
--- a/hdr/bios.asm
+++ /dev/null
@@ -1,17 +0,0 @@
-; Labels for BIOS entry points
-BOOT:   EQU (BIOS+0)
-WBOOT:  EQU (BIOS+3)
-CONST:  EQU (BIOS+6)
-CONIN:  EQU (BIOS+9)
-CONOUT: EQU (BIOS+12)
-LIST:   EQU (BIOS+15)
-PUNCH:  EQU (BIOS+18)
-READER: EQU (BIOS+21)
-HOME:   EQU (BIOS+24)
-SELDSK: EQU (BIOS+27)
-SETTRK: EQU (BIOS+30)
-SETSEC: EQU (BIOS+33)
-SETDMA: EQU (BIOS+36)
-READ:   EQU (BIOS+39)
-WRITE:  EQU (BIOS+42)
-LISTST: EQU (BIOS+45)
diff --git a/hdr/bpb.asm b/hdr/bpb.asm
deleted file mode 100644
index 83c7153..0000000
--- a/hdr/bpb.asm
+++ /dev/null
@@ -1,12 +0,0 @@
-; BPB from first sector on FAT fs, starting 0x0B
-BPB_SS:  EQU 0  ; WORD sector size
-BPB_SC:  EQU 2  ; BYTE sectors per cluster
-BPB_RSC: EQU 3  ; WORD reserved sector count
-BPB_FN:  EQU 5  ; BYTE number of FATs
-BPB_RDE: EQU 6  ; WORD number of root directory entries
-BPB_TS:  EQU 8  ; WORD total number of sectors
-BPB_MI:  EQU 10 ; BYTE medium identifier
-BPB_SF:  EQU 11 ; WORD sectors per FAT
-BPB_SPT: EQU 13 ; WORD sectors per track
-BPB_NOS: EQU 15 ; WORD number of sides/heads
-BPB_PO:  EQU 17 ; DWORD partition offset
diff --git a/hdr/fcb.asm b/hdr/fcb.asm
deleted file mode 100644
index 8bb3852..0000000
--- a/hdr/fcb.asm
+++ /dev/null
@@ -1,10 +0,0 @@
-; File control block
-FCB_DRV: EQU 0  ; BYTE 0=A: 1=B: 2=C: ...
-FCB_NAM: EQU 1  ; 8 BYTES, space padded
-FCB_EXT: EQU 9  ; 3 BYTES, space padded
-FCB_TYP: EQU 12 ; BYTE FCB type
-; TYP=1: regular file
-FCB_BLK: EQU 13 ; current 128b block in sector
-FCB_CLU: EQU 14 ; current sector
-FCB_LFT: EQU 16 ; bytes left to read in current file
-FCB_END: EQU 20 ; FCB length
diff --git a/bdos/dump.asm b/lib/dump.asm
similarity index 52%
rename from bdos/dump.asm
rename to lib/dump.asm
index 115ff7b..5ad8cec 100644
--- a/bdos/dump.asm
+++ b/lib/dump.asm
@@ -1,54 +1,22 @@
-; 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:
-  mov dl, al
-  call CONOUT
-  ret
-
 dump:
   push ax
   push cx
   push dx
   push bx
-  mov dl, 0x0A
-  call CONOUT
-  mov dl, 0x0D
-  call CONOUT
+  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 dl, ':'
-  call CONOUT
-  mov dl, ' '
-  call CONOUT
+  mov al, ':'
+  call putc
+  mov al, ' '
+  call putc
   mov cx, 0x8
 .loop_bin:
   mov ax, [bx]
diff --git a/boot/mbr.asm b/mbr.asm
similarity index 100%
rename from boot/mbr.asm
rename to mbr.asm
diff --git a/pxe.asm b/pxe.asm
new file mode 100644
index 0000000..0808637
--- /dev/null
+++ b/pxe.asm
@@ -0,0 +1,113 @@
+org BASE
+
+main:
+	mov ax, [es:bx+0x0A]
+	mov [cs:pxejmp], ax
+	mov ax, [es:bx+0x0A+2]
+	mov [cs:pxejmp+2], ax
+
+        mov ax, cs
+        mov ds, ax
+        mov si, pxejmp
+        call dump
+
+	mov ax, cs
+	mov ds, ax
+	mov di, pxestat
+	mov bx, 0x0071
+
+	call UsePXEAPI
+
+	mov ax, cs
+	mov ds, ax
+	mov si, pxestat
+	call dump
+	call dump
+
+hlt:	hlt
+	jmp hlt
+
+UsePXEAPI:
+	push ds
+	push di
+	push bx
+	int 3
+	call far [pxejmp]
+	int 3
+	add sp, 6
+	ret
+
+pxejmp: dd 0
+
+pxestat:
+    .Status       dw 0
+    .PacketType   dw 2
+    .BufferSize   dw 0
+       .BufferOff dw 0
+       .BufferSeg dw 0
+    .BufferLimit  dw 0
+
+;tftp_open:
+;    .Status       dw 0
+;    .SIP          dd 0
+;    .GIP          dd 0
+;    .Filename     db "pxe.bs"
+;		  times (128-6) db 0
+;    .Port         dw 0
+;    .PacketSize   dw 0
+
+space:
+	mov al, 0x20
+	jmp putc
+putbc:
+	cmp al, 0x80
+	jnc dot
+	cmp al, 0x20
+	jnc putc
+dot:
+        mov al, '.'
+putc:
+	push ax
+	push bx
+	mov ah, 0x0e
+	xor bx, bx
+	int 0x10
+	pop bx
+	pop ax
+	ret
+
+dump:	push cx
+	mov ax, ds
+	call print16
+	mov al, ':'
+	call putc
+	mov ax, si
+	call print16
+	call space
+	call space
+
+	mov cx, 0x08
+	push si
+.hloop:	lodsb
+	call print8
+	lodsb
+	call print8
+	call space
+	loop .hloop
+	pop si
+	call space
+
+	mov cx, 0x10
+.aloop: lodsb
+	call putbc
+	loop .aloop
+
+	mov al, 0x0A
+	call putc
+	mov al, 0x0D
+	call putc
+	pop cx
+	ret
+
+%include "print.asm"
+%include "printf.asm"
diff --git a/boot/serial.asm b/serial.asm
similarity index 100%
rename from boot/serial.asm
rename to serial.asm
diff --git a/src/utils/em8080.c b/src/utils/em8080.c
deleted file mode 100644
index cc752dd..0000000
--- a/src/utils/em8080.c
+++ /dev/null
@@ -1,518 +0,0 @@
-#include <stdio.h>
-#include <stdint.h>
-#include <string.h>
-#include <stdlib.h>
-
-uint8_t mem[64*1024];
-
-typedef struct flagbits {
-  unsigned int c : 1;
-  unsigned int u1 : 1;
-  unsigned int p : 1;
-  unsigned int u3 : 1;
-
-  unsigned int a : 1;
-  unsigned int u5 : 1;
-  unsigned int z : 1;
-  unsigned int s : 1;
-} flagbits;
-
-typedef struct reg {
-  uint8_t flags;
-  uint8_t a;
-  uint8_t c;
-  uint8_t b;
-  uint8_t e;
-  uint8_t d;
-  uint8_t l;
-  uint8_t h;
-} reg;
-
-typedef struct regp {
-  uint16_t psw;
-  uint16_t bc;
-  uint16_t de;
-  uint16_t hl;
-} regp;
-
-union regset {
-  struct reg reg;
-  struct regp regp;
-} regset;
-
-#define A regset.reg.a
-#define B regset.reg.b
-#define C regset.reg.c
-#define D regset.reg.d
-#define E regset.reg.e
-#define H regset.reg.h
-#define L regset.reg.l
-#define M mem[HL]
-
-#define BC regset.regp.bc
-#define DE regset.regp.de
-#define HL regset.regp.hl
-
-#define flags (*(struct flagbits*)&regset.reg.flags)
-
-uint16_t IP = 0x100;
-uint16_t SP = 0;
-unsigned int tmp;
-
-// Dump registers
-void dump() {
-  printf("\n");
-  printf("A=%02X BC=%04X DE=%04X HL=%04X M=%02X SP=%04X ", A, BC, DE, HL, M, SP);
-  printf("%c", flags.s ? 'S' : '-');
-  printf("%c", flags.z ? 'Z' : '-');
-  printf("%c", flags.a ? 'A' : '-');
-  printf("%c", flags.p ? 'P' : '-');
-  printf("%c", flags.c ? 'C' : '-');
-
-  printf("\n");
-  printf("IP=%04X : %02X %02X\n", IP, mem[IP], mem[IP+1]);
-}
-
-uint8_t imm8() {
-  uint8_t r = *(uint8_t*)&mem[IP];
-  IP++;
-  return r;
-}
-
-uint16_t imm16() {
-  uint16_t r = *(uint16_t*)&mem[IP];
-  IP+=2;
-  return r;
-}
-
-void push(uint16_t v) {
-  SP -= 2;
-  *(uint16_t*)&mem[SP] = v;
-}
-
-uint16_t pop() {
-  uint16_t v = *(uint16_t*)&mem[SP];
-  SP += 2;
-  return v;
-}
-
-void in(uint8_t port) {
-
-}
-
-void out(uint8_t port) {
-
-}
-
-int has_even_parity(uint8_t x){
-  unsigned int count = 0, i, b = 1;
-
-  for(i = 0; i < 8; i++){
-      if( x & (b << i) ){count++;}
-  }
-
-  if( (count % 2) ){return 0;}
-  return 1;
-}
-
-void cpm_syscall(int number) {
-  switch(number) {
-  case 0:
-    exit(0);
-    break;
-  case 2:
-    printf("%c", E);
-    break;
-  case 0x0C:
-    H=0x02;
-    L=0x00;
-    break;;
-  default:
-    fprintf(stderr, "Fatal: Unhandled CP/M syscall C=%02Xh\n", number);
-    exit(1);
-  }
-}
-
-void call(uint16_t v) {
-  switch(v) {
-  case 0:
-    exit(0);
-    break;;
-  case 5:
-    cpm_syscall(C);
-    break;;
-  default:
-    push(IP);
-    IP=v;
-    break;
-  }
-}
-
-void interrupt(int number) {
-  call(number << 3);
-}
-
-#define add16c(a, b) \
-  tmp = a + b; \
-  flags.c = (tmp >> 16) & 1
-
-#define unarync(a, op) \
-  tmp=a; \
-  tmp op; \
-  flags.p = has_even_parity(tmp & 8); \
-  flags.z = !(tmp); \
-  flags.s = (tmp >> 7) & 1; \
-  a=tmp
-
-#define aritht(a, op, b) \
-  tmp=a; \
-  tmp=a op b; \
-  flags.c = (tmp >> 8) & 1; \
-  flags.p = has_even_parity(tmp & 8); \
-  flags.z = !(tmp); \
-  flags.s = (tmp >> 7) & 1;
-
-#define arith(a, op, b) \
-  aritht(a, op, b); \
-  a=tmp
-
-// Execute a single instruction
-void step() {
-  uint8_t opcode = mem[IP];
-  IP++;
-  switch(opcode) {
-  case 0x00: break;;
-  case 0x01: BC=imm16(); break;;
-  case 0x02: mem[BC]=A; break;;
-  case 0x03: BC++;
-  case 0x04: unarync(B, ++); break;;
-  case 0x05: unarync(B, --); break;;
-  case 0x06: B=imm8(); break;;
-  case 0x07: tmp=A; A = A << 1 | flags.c; flags.c = tmp >> 7; break;;
-
-  case 0x09: HL=add16c(HL,BC); break;;
-  case 0x0a: A=mem[BC]; break;;
-  case 0x0b: BC--;
-  case 0x0c: unarync(B, ++); break;;
-  case 0x0d: unarync(B, --); break;;
-  case 0x0e: C=imm8(); break;;
-
-  case 0x11: DE=imm16(); break;;
-  case 0x12: mem[DE]=A; break;;
-  case 0x13: DE++;
-  case 0x14: unarync(D, ++); break;;
-  case 0x15: unarync(D, --); break;;
-  case 0x16: D=imm8(); break;;
-
-  case 0x19: HL=add16c(HL,DE); break;;
-  case 0x1a: A=mem[DE]; break;;
-  case 0x1b: DE--;
-  case 0x1c: unarync(E, ++); break;;
-  case 0x1d: unarync(E, --); break;;
-  case 0x1e: E=imm8(); break;;
-
-  case 0x21: HL=imm16(); break;;
-  case 0x22: *(uint16_t*)&mem[imm16()]=HL; break;;
-  case 0x23: HL++;
-  case 0x24: unarync(H, ++); break;;
-  case 0x25: unarync(H, --); break;;
-  case 0x26: H=imm8(); break;;
-
-  case 0x29: HL=add16c(HL,HL); break;;
-  case 0x2a: HL=*(uint16_t*)&mem[imm16()]; break;;
-  case 0x2b: HL--;
-  case 0x2c: unarync(L, ++); break;;
-  case 0x2d: unarync(L, --); break;;
-  case 0x2e: L=imm8(); break;;
-  case 0x2f: A=~A; break;;
-
-  case 0x31: SP=imm16(); break;;
-  case 0x32: mem[imm16()]=A; break;;
-  case 0x33: SP++;
-  case 0x34: unarync(M, ++); break;;
-  case 0x35: unarync(M, --); break;;
-  case 0x36: M=imm8(); break;;
-  case 0x37: flags.c = 1; break;;
-
-  case 0x39: HL=add16c(HL,SP); break;;
-  case 0x3a: A=mem[imm16()]; break;;
-  case 0x3b: SP--;
-  case 0x3c: unarync(A, ++); break;;
-  case 0x3d: unarync(A, --); break;;
-  case 0x3e: A=imm8(); break;;
-  case 0x3f: flags.c = !flags.c; break;;
-
-  case 0x40: B=B; break;;
-  case 0x41: B=C; break;;
-  case 0x42: B=D; break;;
-  case 0x43: B=E; break;;
-  case 0x44: B=H; break;;
-  case 0x45: B=L; break;;
-  case 0x46: B=M; break;;
-  case 0x47: B=A; break;;
-
-  case 0x48: C=B; break;;
-  case 0x49: C=C; break;;
-  case 0x4a: C=D; break;;
-  case 0x4b: C=E; break;;
-  case 0x4c: C=H; break;;
-  case 0x4d: C=L; break;;
-  case 0x4e: C=M; break;;
-  case 0x4f: C=A; break;;
-
-  case 0x50: D=B; break;;
-  case 0x51: D=C; break;;
-  case 0x52: D=D; break;;
-  case 0x53: D=E; break;;
-  case 0x54: D=H; break;;
-  case 0x55: D=L; break;;
-  case 0x56: D=M; break;;
-  case 0x57: D=A; break;;
-
-  case 0x58: E=B; break;;
-  case 0x59: E=C; break;;
-  case 0x5a: E=D; break;;
-  case 0x5b: E=E; break;;
-  case 0x5c: E=H; break;;
-  case 0x5d: E=L; break;;
-  case 0x5e: E=M; break;;
-  case 0x5f: E=A; break;;
-
-  case 0x60: H=B; break;;
-  case 0x61: H=C; break;;
-  case 0x62: H=D; break;;
-  case 0x63: H=E; break;;
-  case 0x64: H=H; break;;
-  case 0x65: H=L; break;;
-  case 0x66: H=M; break;;
-  case 0x67: H=A; break;;
-
-  case 0x68: L=B; break;;
-  case 0x69: L=C; break;;
-  case 0x6a: L=D; break;;
-  case 0x6b: L=E; break;;
-  case 0x6c: L=H; break;;
-  case 0x6d: L=L; break;;
-  case 0x6e: L=M; break;;
-  case 0x6f: L=A; break;;
-
-  case 0x70: M=B; break;;
-  case 0x71: M=C; break;;
-  case 0x72: M=D; break;;
-  case 0x73: M=E; break;;
-  case 0x74: M=H; break;;
-  case 0x75: M=L; break;;
-  case 0x76: exit(0); break;;
-  case 0x77: M=A; break;;
-
-  case 0x78: A=B; break;;
-  case 0x79: A=C; break;;
-  case 0x7a: A=D; break;;
-  case 0x7b: A=E; break;;
-  case 0x7c: A=H; break;;
-  case 0x7d: A=L; break;;
-  case 0x7e: A=M; break;;
-  case 0x7f: A=A; break;;
-
-  case 0x80: arith(A, +, B); break;;
-  case 0x81: arith(A, +, C); break;;
-  case 0x82: arith(A, +, D); break;;
-  case 0x83: arith(A, +, E); break;;
-  case 0x84: arith(A, +, H); break;;
-  case 0x85: arith(A, +, L); break;;
-  case 0x86: arith(A, +, M); break;;
-  case 0x87: arith(A, +, A); break;;
-
-  case 0x88: arith(A, +flags.c+, B); break;;
-  case 0x89: arith(A, +flags.c+, C); break;;
-  case 0x8A: arith(A, +flags.c+, D); break;;
-  case 0x8B: arith(A, +flags.c+, E); break;;
-  case 0x8C: arith(A, +flags.c+, H); break;;
-  case 0x8D: arith(A, +flags.c+, L); break;;
-  case 0x8E: arith(A, +flags.c+, M); break;;
-  case 0x8F: arith(A, +flags.c+, A); break;;
-
-  case 0x90: arith(A, -, B); break;;
-  case 0x91: arith(A, -, C); break;;
-  case 0x92: arith(A, -, D); break;;
-  case 0x93: arith(A, -, E); break;;
-  case 0x94: arith(A, -, H); break;;
-  case 0x95: arith(A, -, L); break;;
-  case 0x96: arith(A, -, M); break;;
-  case 0x97: arith(A, -, A); break;;
-
-  case 0x98: arith(A, -flags.c-, B); break;;
-  case 0x99: arith(A, -flags.c-, C); break;;
-  case 0x9A: arith(A, -flags.c-, D); break;;
-  case 0x9B: arith(A, -flags.c-, E); break;;
-  case 0x9C: arith(A, -flags.c-, H); break;;
-  case 0x9D: arith(A, -flags.c-, L); break;;
-  case 0x9E: arith(A, -flags.c-, M); break;;
-  case 0x9F: arith(A, -flags.c-, A); break;;
-
-  case 0xA0: arith(A, &, B); break;;
-  case 0xA1: arith(A, &, C); break;;
-  case 0xA2: arith(A, &, D); break;;
-  case 0xA3: arith(A, &, E); break;;
-  case 0xA4: arith(A, &, H); break;;
-  case 0xA5: arith(A, &, L); break;;
-  case 0xA6: arith(A, &, M); break;;
-  case 0xA7: arith(A, &, A); break;;
-
-  case 0xA8: arith(A, ^, B); break;;
-  case 0xA9: arith(A, ^, C); break;;
-  case 0xAA: arith(A, ^, D); break;;
-  case 0xAB: arith(A, ^, E); break;;
-  case 0xAC: arith(A, ^, H); break;;
-  case 0xAD: arith(A, ^, L); break;;
-  case 0xAE: arith(A, ^, M); break;;
-  case 0xAF: arith(A, ^, A); break;;
-
-  case 0xB0: arith(A, |, B); break;;
-  case 0xB1: arith(A, |, C); break;;
-  case 0xB2: arith(A, |, D); break;;
-  case 0xB3: arith(A, |, E); break;;
-  case 0xB4: arith(A, |, H); break;;
-  case 0xB5: arith(A, |, L); break;;
-  case 0xB6: arith(A, |, M); break;;
-  case 0xB7: arith(A, |, A); break;;
-
-  case 0xB8: aritht(A, -, B); break;;
-  case 0xB9: aritht(A, -, C); break;;
-  case 0xBA: aritht(A, -, D); break;;
-  case 0xBB: aritht(A, -, E); break;;
-  case 0xBC: aritht(A, -, H); break;;
-  case 0xBD: aritht(A, -, L); break;;
-  case 0xBE: aritht(A, -, M); break;;
-  case 0xBF: aritht(A, -, A); break;;
-
-  case 0xC0: if (!flags.z) IP=pop(); break;;
-  case 0xC1: BC=pop(); break;;
-  case 0xC2: tmp=imm16(); if (!flags.z) IP=tmp; break;;
-  case 0xC3: IP=imm16(); break;;
-  case 0xC4: tmp=imm16(); if (!flags.z) call(tmp); break;;
-  case 0xC5: push(BC); break;;
-  case 0xC6: arith(A, +, imm8()); break;;
-  case 0xC7: interrupt(0); break;;
-
-  case 0xC8: if (flags.z) IP=pop(); break;;
-  case 0xC9: IP=pop(); break;;
-  case 0xCA: tmp=imm16(); if (flags.z) IP=tmp; break;;
-  case 0xCC: tmp=imm16(); if (flags.z) call(tmp); break;;
-  case 0xCD: call(imm16()); break;;
-  case 0xCE: arith(A, +flags.c+, imm8()); break;;
-  case 0xCF: interrupt(1); break;;
-
-  case 0xD0: if (!flags.c) IP=pop(); break;;
-  case 0xD1: DE=pop(); break;;
-  case 0xD2: tmp=imm16(); if (!flags.c) IP=tmp; break;;
-  case 0xD3: out(imm8()); break;;
-  case 0xD4: tmp=imm16(); if (!flags.c) call(tmp); break;;
-  case 0xD5: push(DE); break;;
-  case 0xD6: arith(A, -, imm8()); break;;
-  case 0xD7: interrupt(2); break;;
-
-  case 0xD8: if (flags.c) IP=pop(); break;;
-  case 0xDA: tmp=imm16(); if (flags.c) IP=tmp; break;;
-  case 0xDB: in(imm8()); break;;
-  case 0xDC: tmp=imm16(); if (flags.c) call(tmp); break;;
-  case 0xDE: arith(A, -flags.c-, imm8()); break;;
-  case 0xDF: interrupt(3); break;;
-
-  case 0xE0: if (!flags.p) IP=pop(); break;;
-  case 0xE1: HL=pop(); break;;
-  case 0xE2: tmp=imm16(); if (!flags.p) IP=tmp; break;;
-  case 0xE3: tmp=HL; HL=pop(); push(tmp); break;;
-  case 0xE4: tmp=imm16(); if (!flags.p) call(tmp); break;;
-  case 0xE5: push(HL); break;;
-  case 0xE6: arith(A, &, imm8()); break;;
-  case 0xE7: interrupt(4); break;;
-
-  case 0xE8: if (flags.p) IP=pop(); break;;
-  case 0xE9: IP=HL; break;;
-  case 0xEA: tmp=imm16(); if (flags.p) IP=tmp; break;;
-  case 0xEB: tmp=HL; HL=DE; DE=tmp;; break;;
-  case 0xEC: tmp=imm16(); if (flags.p) call(tmp); break;;
-  case 0xEE: arith(A, ^, imm8()); break;;
-  case 0xEF: interrupt(5); break;;
-
-  case 0xF0: if (!flags.s) IP=pop(); break;;
-  case 0xF1: regset.regp.psw=pop(); break;;
-  case 0xF2: tmp=imm16(); if (!flags.s) IP=tmp; break;;
-  case 0xF4: tmp=imm16(); if (!flags.s) call(tmp); break;;
-  case 0xF5: push(regset.regp.psw); break;;
-  case 0xF6: arith(A, |, imm8()); break;;
-  case 0xF7: interrupt(6); break;;
-
-  case 0xF8: if (flags.s) IP=pop(); break;;
-  case 0xF9: SP=HL; break;;
-  case 0xFA: tmp=imm16(); if (flags.s) IP=tmp; break;;
-  case 0xFC: tmp=imm16(); if (flags.s) call(tmp); break;;
-  case 0xFE: aritht(A, -, imm8()); break;;
-  case 0xFF: interrupt(7); break;;
-
-  default:
-    IP--;
-    dump();
-    fprintf(stderr, "Invalid opcode at IP=%04X\n", IP);
-    exit(1);
-    break;
-  }
-}
-
-void copy_cmdline(char* str) {
-  int i, c;
-  uint8_t *len = &mem[0x80];
-  char* ptr = (char*)&mem[0x81];
-  c = strlen(str);
-  // Clip at max length
-  if (c>0x7E) {
-    fprintf(stderr, "Command line too long, max is 126 bytes\n");
-    exit(1);
-  }
-  memcpy(ptr, str, c);
-  ptr[c]=0x0D;
-  *len=c;
-}
-
-int main(int argc, char** argv) {
-  memset(&mem, sizeof(mem), 0);
-  // Prepare default exit into int 20h
-  mem[0]=0x76;
-  push(0);
-
-  argc--;
-  argv++;
-
-  while(argc && argv[0][0]=='-') {
-    switch(argv[0][1]) {
-    default:
-      fprintf(stderr, "Unknown option %s\n", argv[0]);
-      exit(1);
-      break;
-    }
-    argc--;
-    argv++;
-  }
-
-  if (argc) {
-    FILE* fd = fopen(argv[0], "r");
-    fread(mem + IP, 1, sizeof(mem) - IP, fd);
-    argc--;
-    argv++;
-  } else {
-    fprintf(stderr, "No COM file specified\n");
-    exit(1);
-  }
-
-  if (argc) {
-    copy_cmdline(argv[0]);
-  } else {
-    copy_cmdline("");
-  }
-
-  while(1) {
-    dump();
-    step();
-  }
-}
diff --git a/src/vga11.asm b/vga11.asm
similarity index 100%
rename from src/vga11.asm
rename to vga11.asm