diff --git a/Makefile b/Makefile
index 4f81fe1b..dbd927c5 100644
--- a/Makefile
+++ b/Makefile
@@ -2,14 +2,13 @@ TOPDIR = $(realpath .)
 
 SUBDIRS = tools lib system effects intro
 EXTRA-FILES = tags cscope.out
-CLEAN-FILES = bootloader.bin
+CLEAN-FILES = bootloader.bin a500rom.bin addchip.bootblock.bin
 
-all: a500rom.bin bootloader.bin build
+all: a500rom.bin bootloader.bin addchip.bootblock.bin build
 
-include $(TOPDIR)/build/common.mk
+addchip.bootblock.bin: VASMFLAGS += -phxass -cnop=0
 
-a500rom.bin: ASFLAGS += -phxass
-bootloader.bin: ASFLAGS += -phxass
+include $(TOPDIR)/build/common.mk
 
 FILES := $(shell find include lib system -type f -iname '*.[ch]')
 
diff --git a/addchip.bootblock.asm b/addchip.bootblock.asm
new file mode 100644
index 00000000..9abe5444
--- /dev/null
+++ b/addchip.bootblock.asm
@@ -0,0 +1,163 @@
+; Downloaded from https://github.com/earok/close-and-run-amiga68k
+
+        include 'lvo/exec_lib.i'
+        include 'lvo/intuition_lib.i'
+
+Height		EQU	50
+zeropage	EQU	$100
+
+RT_INIT		EQU	$16
+lib_Version	EQU	$14
+LibList		EQU	$17a
+io_Device	EQU	$14
+KS20		EQU	36
+
+
+boot		dc.b	'DOS',0
+		dc.b	'r05s'				;tagged
+		dc.l	880
+
+start		movem.l	d2-d5/a2/a5,-(a7)
+		
+		moveq	#-1,d0				;disable externals drives
+		movea.l	io_Device(a1),a1
+		movea.l	$3c(a1),a1			;the 'old times mod'
+		lea	$34(a1),a1
+		move.l	d0,(a1)+			;df1:
+		move.l	d0,(a1)+			;df2:
+		move.l	d0,(a1)				;and why not.. df3:
+		
+		moveq	#0,d4
+		cmpi.w	#KS20,lib_Version(a6)		;fork
+		shs	d4
+
+		lea	zeropage.w,a5			;a0jmp
+		move.l	a5,d5
+		lea	a0jmp(pc),a0
+		moveq	#(endscreen-a0jmp)/4-1,d0
+_l		move.l	(a0)+,(a5)+
+		dbf	d0,_l				;at end a5=zerobss
+		
+		movea.l	LibList(a6),a0
+		lea	intuitionlib(pc),a1
+		jsr	_LVOFindName(a6)
+		move.l	d0,(a5)+			;intuitionbase
+		beq.b	_exit
+		
+		lea	intuitionlib(pc),a1
+		jsr	_LVOFindResident(a6)
+		tst.l	d0				;can be omitted..
+		beq.b	_exit
+		
+		lea	wbname(pc),a1			;'Workbench Screen',0
+		moveq	#doslib-wbname,d1		;strlen
+		bsr.b	findstrres
+		move.l	a0,title-(zerobss+4)(a5)
+
+		move.l	d4,(a5)+			;v36?
+		beq.b	notags
+		moveq	#10,d1				;strlen
+		clr.b	-1(a1,d1.w)			;'Workbench',0
+		bsr.b	findstrres
+		move.l	a0,pubname-(zerobss+8)(a5)
+		
+		
+notags		lea	doslib(pc),a1
+		jsr	_LVOFindResident(a6)
+		tst.l	d0
+		beq.b	_exit
+		movea.l	d0,a1
+		move.l	RT_INIT(a1),(a5)		;dosinit
+
+		tst.l	d4				;v36?
+		beq.b	_done
+		move.w	#Height,_h-(zerobss+8)(a5)	;set height for >=v36
+		jsr	_LVOCacheClearU(a6)
+
+_done		moveq	#-1,d0
+_exit		movea.l	d5,a0				;a0jmp
+		not.l	d0
+		movem.l	(sp)+,d2-d5/a2/a5
+		rts
+
+
+;input:		d0=resident base
+;		d1=strlen
+;		a1=string to search
+;output:	a0=&str
+;used:		d2/d3/a2 saved by main, a0 as return code
+
+findstrres	movea.l	d0,a0
+_search		move.w	d1,d2
+		subq.w	#2,d2			;-(dbne,+)
+		movea.l	a1,a2
+		move.b	(a2)+,d3
+_s1		cmp.b	(a0)+,d3
+		bne.b	_s1
+_s2		cmpm.b	(a2)+,(a0)+
+		dbne	d2,_s2
+		bne.b	_search
+		suba.l	d1,a0
+		rts
+
+wbname		dc.b	'Workbench Screen',0
+doslib		dc.b	'dos.library',0
+intuitionlib	dc.b	'intuition.library',0
+
+		cnop	0,4
+
+fakechecksum	dc.l	$b99c2e9d
+
+a0jmp		lea	zerobss(pc),a5
+		movea.l	(a5)+,a6		;intuitionbase
+		jsr	_LVOOpenIntuition(a6)	;KS1.x mandatory (undocumented)
+		lea	wbscreen(pc),a0
+		tst.l	(a5)+
+		bne.b	v36
+		jsr	_LVOOpenScreen(a6)
+		bra.s	dos
+v36		lea	tagitems(pc),a1		;Workbench need to be Pub
+		jsr	_LVOOpenScreenTagList(a6)
+dos		movea.l	(a5),a0			;dosinit
+		jmp	(a0)			;start amigados
+		cnop	0,4
+		
+tagitems	dc.l	$8000002f		;SA_PubName
+pubname		dc.l	0			;'Workbench',0		
+;		dc.l	0			;TAG_DONE (fixed to wbscreen struct)
+		;
+wbscreen	dc.w	0			;WORD LeftEdge
+		dc.w	0			;WORD TopEdge
+		dc.w	640			;WORD Widht
+_h		dc.w	200			;WORD Height (KS1.x min height)
+		dc.w	1			;WORD Depth
+		dc.b	0,1			;UBYTE DetailPen, BlockPen
+		dc.w	$8000			;UWORD ViewModes -> HIRES
+		dc.w	1			;UWORD Type -> WBENCHSCREEN
+		dc.l	0			;struct TextAttr *Font, defaults
+title		dc.l	0			;UBYTE *DefaultTitle, ROM
+		dc.l	0			;struct Gadget *Gadgets, UNUSED
+		dc.l	0			;struct BitMap *CustomBitMap, NULL
+endscreen	;
+		;
+zerobss		;				;(fixed to wbscreen struct)
+;intuitionbase	;zerobss+0
+;		ds.l	1
+;stag		;zerobss+4
+;		ds.l	1
+;dosinit	;zerobss+8
+;		ds.l	1
+endzero
+
+		cnop	0,16
+ver		dc.b	'$VER: addchip.bootblock 1.1 (27.07.2017) by ross',0
+
+		cnop	0,16
+message		dc.b	' This code snippet allows you to regain some precious chip ram. '
+		cnop	0,16
+		dc.b	'*       Greetings to all Evergreen Amiga Board members!        *'
+		even
+		
+		END
+
+; vim: ft=asm68k:ts=8:sw=8:et
diff --git a/build/common.mk b/build/common.mk
index 0e71fe0e..8d4f5cb2 100644
--- a/build/common.mk
+++ b/build/common.mk
@@ -28,14 +28,19 @@ LDSCRIPT := $(TOPDIR)/system/amiga.lds
 
 # Don't reload library base for each call
 CPPFLAGS += -D__CONSTLIBBASEDECL__=const
+CPPFLAGS += -DCHIPMEM_KB=$(CHIPMEM) -DFASTMEM_KB=$(FASTMEM) -DLOGOUT=$(LOGOUT)
 
-# Default configuration
-FRAMES_PER_ROW ?= 6
+include $(TOPDIR)/config.mk
 
+ifeq ($(UAE), 1)
 CPPFLAGS += -DUAE
+endif
+
+ifeq ($(AMIGAOS), 1)
+CPPFLAGS += -DAMIGAOS
+endif
 
-# Pass "VERBOSE=1" at command line to display command being invoked by GNU Make
-ifneq ($(VERBOSE), 1)
+ifeq ($(VERBOSE), 0)
 .SILENT:
 QUIET := --quiet
 endif
diff --git a/build/effect.mk b/build/effect.mk
index 8c499737..35830abc 100644
--- a/build/effect.mk
+++ b/build/effect.mk
@@ -12,9 +12,14 @@ CRT0 = $(TOPDIR)/system/crt0.o
 MAIN ?= $(TOPDIR)/effects/main.o
 BOOTLOADER = $(TOPDIR)/bootloader.bin
 ROMSTARTUP = $(TOPDIR)/a500rom.bin
+BOOTBLOCK = $(TOPDIR)/addchip.bootblock.bin
 
-EXTRA-FILES += $(DATA_GEN) $(EFFECT).img $(EFFECT).adf $(EFFECT).rom
-CLEAN-FILES += $(DATA_GEN) $(EFFECT).exe $(EFFECT).exe.dbg $(EFFECT).exe.map 
+EXTRA-FILES += $(DATA_GEN) $(EFFECT).adf
+CLEAN-FILES += $(DATA_GEN) $(EFFECT).exe $(EFFECT).exe.dbg $(EFFECT).exe.map
+
+ifeq ($(AMIGAOS), 0)
+EXTRA-FILES += $(EFFECT).img $(EFFECT).rom
+endif
 
 all: build
 
@@ -66,6 +71,7 @@ data/%.c: data/%.sync
 	@echo "[SYNC] $(DIR)$< -> $(DIR)$@"
 	$(SYNC2C) $(SYNC2C.$*) $< > $@ || (rm -f $@ && exit 1)
 
+ifeq ($(AMIGAOS), 0)
 %.img: %.exe $(DATA) $(DATA_GEN)
 	@echo "[IMG] $(addprefix $(DIR),$*.exe $(DATA) $(DATA_GEN)) -> $(DIR)$@"
 	$(FSUTIL) create $@ $(filter-out %bootloader.bin,$^)
@@ -77,6 +83,14 @@ data/%.c: data/%.sync
 %.rom: %.img $(ROMSTARTUP)
 	@echo "[ROM] $(DIR)$< -> $(DIR)$@"
 	$(ROMUTIL) $(ROMSTARTUP) $< $@ 
+else
+%.adf: %.exe $(BOOTBLOCK)
+	@echo "[ADF] $(DIR)$< -> $(DIR)$@"
+	echo $< > startup-sequence
+	xdftool $@ format dos + write $< + makedir s + write startup-sequence s
+	dd if=$(BOOTBLOCK) of=$@ conv=notrunc status=none
+	rm startup-sequence
+endif
 
 # Default debugger - can be changed by passing DEBUGGER=xyz to make.
 DEBUGGER ?= gdb
@@ -97,4 +111,4 @@ $(TOPDIR)/gdb-dashboard:
 	make -C $(TOPDIR) gdb-dashboard
 
 .PHONY: run debug run-floppy debug-floppy
-.PRECIOUS: $(BOOTLOADER) $(EFFECT).img
+.PRECIOUS: $(BOOTLOADER) $(BOOTBLOCK) $(EFFECT).img
diff --git a/config.mk b/config.mk
new file mode 100644
index 00000000..c7efd1c8
--- /dev/null
+++ b/config.mk
@@ -0,0 +1,29 @@
+# 1 => Use fs-uae dependant features i.e. call-traps (see `include/uae.h`)
+#      to aid debugging and profiling. This may render executable files
+#      unusable (most likely crash) on real hardware.
+# 0 => Disable use of aforementioned features. Required for a release!
+UAE := 1
+
+# [only when UAE=0] Redirect diagnostic and log messages to:
+# 0 => null output (drop messages)
+# 1 => parallel port
+# 2 => serial port
+LOGOUT := 2
+
+# 1 => Make executable files compatible with AmigaOS. Created ADFs will
+#      be formatted with Old Filesystem (KS1.3) and contain special bootblock
+#      that maximizes amount of chip memory. Executable file will be started
+#      automatically facilitating `startup-sequence` feature of AmigaDOS.
+# 0 => Executable files must be started from ROM or ADF since they require
+#      custom environment created by bootstrap code.
+AMIGAOS := 0
+
+# [only when AMIGAOS=1] Amount of chip and fast (or public) memory 
+# (in kilobytes!) passed to our custom memory allocator.
+# To calculate total memory taken after an executable file
+# is loaded into memory please use `m68k-amigaos-objdump` tool.
+CHIPMEM := 160
+FASTMEM := 288
+
+# Pass "VERBOSE=1" at command line to display command being invoked by GNU Make
+VERBOSE ?= 0
diff --git a/include/custom_regdef.h b/include/custom_regdef.h
index 8a269424..78cfb3e8 100644
--- a/include/custom_regdef.h
+++ b/include/custom_regdef.h
@@ -147,6 +147,8 @@ struct Custom {
 #define intena 0x09a
 #define intreqr 0x01e
 #define intreq 0x09c
+#define serdatr 0x018
+#define serdat 0x030
 
 #endif
 
diff --git a/include/system/debug.h b/include/system/debug.h
index 60df499d..0fc9698e 100644
--- a/include/system/debug.h
+++ b/include/system/debug.h
@@ -8,10 +8,15 @@
 #define Log(...) UaeLog(__VA_ARGS__);
 #define Panic(...) { UaeLog(__VA_ARGS__); PANIC(); }
 #else
+#if LOGOUT > 0
 void Log(const char *format, ...)
   __attribute__ ((format (printf, 1, 2)));
 __noreturn void Panic(const char *format, ...)
   __attribute__ ((format (printf, 1, 2)));
+#else
+#define Log(...)
+#define Panic(...) HALT()
+#endif
 #endif
 
 #ifdef _SYSTEM
diff --git a/requirements.txt b/requirements.txt
index 97629e19..ec7528b8 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -5,3 +5,4 @@ pycodestyle
 pygments
 zopflipy
 blessings
+amitools
diff --git a/system/Makefile b/system/Makefile
index c0ea24e9..798197d7 100644
--- a/system/Makefile
+++ b/system/Makefile
@@ -1,7 +1,5 @@
 TOPDIR := $(realpath ..)
 
-# AMIGAOS => save & restore AmigaOS context
-#            (for intros or trackmos that can be launched from AmigaOS)
 CPPFLAGS += -D_SYSTEM
 
 LIBNAME := system
@@ -9,7 +7,8 @@ SOURCES := \
 	amigaos.c \
 	autoinit.c \
 	debug.c \
-	debug-putchar.S \
+	dputchar.S \
+	kputchar.S \
 	effect.c \
 	loader.c \
 	profiler.c \
diff --git a/system/amigaos.c b/system/amigaos.c
index 18e540b7..385638bf 100644
--- a/system/amigaos.c
+++ b/system/amigaos.c
@@ -40,8 +40,8 @@ static ExcVecT oldExcVec;
 static void *oldSysStack;
 
 /* Memory for framework allocator. */
-static __aligned(4) __bss_chip char ChipMem[160 * 1024];
-static __aligned(4) char FastMem[288 * 1024];
+static __aligned(4) __bss_chip char ChipMem[CHIPMEM_KB * 1024];
+static __aligned(4) char FastMem[FASTMEM_KB * 1024];
 
 /* Normally BootDataT is provided by the boot loader. Since we were started
  * from AmigaOS we have to fill this structure and pass it to Loader. */
diff --git a/system/debug-putchar.S b/system/debug-putchar.S
deleted file mode 100644
index 4aacd633..00000000
--- a/system/debug-putchar.S
+++ /dev/null
@@ -1,19 +0,0 @@
-# Reliable transfers may only happen 3 or more E-cycles basis.
-# http://lallafa.de/blog/2015/09/amiga-parallel-port-how-fast-can-you-go/
-
-#include <asm.h>
-#include <cia_regdef.h>
-
-# [a0] ciab, ciaa = ciab + $1001
-ENTRY(DPutChar)
-.Loop:  btst    #CIAB_PRTRBUSY,(a0)     /* is printer buffer empty ? */
-        jne     .Loop
-
-        st.b    ciaddrb+0x1001(a0)      /* set direction to out */
-        move.b  d0,ciaprb+0x1001(a0)	/* write the data */
-        tst.b   (a0)                    /* waste 2 E-cycles */
-        tst.b   (a0)
-        rts
-END(DPutChar)
-
-# vim: ft=gas:ts=8:sw=8:noet:
diff --git a/system/debug.c b/system/debug.c
index f003840a..382a5107 100644
--- a/system/debug.c
+++ b/system/debug.c
@@ -1,17 +1,33 @@
 #include "debug.h"
 
-#ifndef UAE
+#if !defined(UAE) && LOGOUT > 0
 #include <stdarg.h>
 #include <stdio.h>
+
+#if LOGOUT == 1
 #include <system/cia.h>
 
 extern void DPutChar(void *ptr, char data);
 
+#define PUTCHAR DPutChar
+#define AUXDATA ciab
+#endif 
+
+#if LOGOUT == 2
+#include <custom.h>
+
+extern void KPutChar(void *ptr, char data);
+
+#define PUTCHAR KPutChar
+#define AUXDATA custom
+#endif
+
 void Log(const char *format, ...) {
   va_list args;
 
   va_start(args, format);
-  kvprintf(DPutChar, (void *)ciab, format, args);
+  kvprintf(PUTCHAR, (void *)AUXDATA, format, args);
+
   va_end(args);
 }
 
@@ -19,7 +35,7 @@ __noreturn void Panic(const char *format, ...) {
   va_list args;
 
   va_start(args, format);
-  kvprintf(DPutChar, (void *)ciab, format, args);
+  kvprintf(PUTCHAR, (void *)AUXDATA, format, args);
   va_end(args);
 
   PANIC();
diff --git a/system/dputchar.S b/system/dputchar.S
new file mode 100644
index 00000000..d92d2a4f
--- /dev/null
+++ b/system/dputchar.S
@@ -0,0 +1,36 @@
+# Reliable transfers may only happen 3 or more E-cycles basis.
+# http://lallafa.de/blog/2015/09/amiga-parallel-port-how-fast-can-you-go/
+
+#include <asm.h>
+#include <cia_regdef.h>
+
+/* It's a reimplementation of PRawPutChar in ddebug.lib from NDK3.2 */
+
+# [a0.l] ciab, ciaa = ciab + $1001
+# [d0.b] character
+ENTRY(DPutChar)
+        tst.b   d0              /* don't send character if it's zero */
+        beq.s   .Quit
+
+        move.w  d0,-(sp)
+        cmp.b   #10,d0          /* send '\r' first if the character is `\n` */
+        bne.s   .NoNL
+        moveq   #13,d0
+        bsr.s   .Send
+        tst.b   (a0)                    /* waste single E-cycle */
+.NoNL:  move.w  (sp)+,d0
+
+.Send:  tst.b   (a0)                    /* waste 2 E-cycles */
+        tst.b   (a0)
+.Wait:  btst    #CIAB_PRTRBUSY,(a0)     /* is printer buffer empty ? */
+        bne.s   .Wait
+
+        st.b    ciaddrb+0x1001(a0)      /* set direction to out */
+        move.b  d0,ciaprb+0x1001(a0)	/* write the data */
+        tst.b   (a0)                    /* waste another 2 E-cycles */
+        tst.b   (a0)
+
+.Quit:  rts
+END(DPutChar)
+
+# vim: ft=gas:ts=8:sw=8:noet:
diff --git a/system/kputchar.S b/system/kputchar.S
new file mode 100644
index 00000000..008e398a
--- /dev/null
+++ b/system/kputchar.S
@@ -0,0 +1,27 @@
+#include <asm.h>
+#include <custom_regdef.h>
+
+# [a0.l] custom
+# [d0.b] character
+ENTRY(KPutChar)
+        tst.b   d0              /* don't send character if it's zero */
+        beq.s   .Quit
+
+        move.w  d0,-(sp)
+        cmp.b   #10,d0          /* send '\r' first if the character is `\n` */
+        bne.s   .NoNL
+        moveq   #13,d0
+        bsr.s   .Send
+.NoNL:  move.w  (sp)+,d0
+
+.Send:  move.w  #0x100,d1       /* add stop bit */
+        move.b  d0,d1
+
+.Wait:  btst.b  #5,serdatr(a0)  /* loop until transmit buffer empty */
+        beq.s   .Wait
+        move.w  d1,serdat(a0)   /* send the character */
+
+.Quit:  rts
+END(KPutChar)
+
+# vim: ft=gas:ts=8:sw=8:noet: