diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..09af0a0
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "mc8051fun"]
+	path = mc8051fun
+	url = https://git.planix.org/7u83/mc8051fun.git
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..a13d35c
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,65 @@
+-include defs.mak
+
+SDCC ?= sdcc
+SDAR ?= sdar
+SDAS ?= sdas
+
+STCCODESIZE ?= 8192
+SDCCOPTS ?= 
+SDCCREV ?= -Dstc15f204ea
+STCGAL ?= stcgal 
+STCGALOPTS ?= 
+STCGALPORT ?= /dev/ttyUSB0
+STCGALPROT ?= auto
+FLASHFILE ?= main.ihx
+PRGOPTS ?= 
+
+
+SYSCLK ?= 11059
+FOSC ?=11059200L
+CFLAGS ?= 
+
+LIBSRC = 
+
+LIBNAME = mc8051fun/mc8051fun.lib
+
+PRGSRC = calc.c
+
+PRGOBJ =$(patsubst %.c,%.rel, $(PRGSRC))
+
+$(FLASHFILE): $(LIBNAME) $(PRGOBJ) 
+	$(SDCC) -o $(FLASHFILE) $(SDCCOPTS) $(SDCCREV) $(CFLAGS) $(PRGOBJ) $(LIBNAME)
+
+
+$(LIBNAME): $(LIBOBJ)
+	$(SDAR) -rc $(LIBNAME) $(LIBOBJ)
+#all: 
+#	make uart2.ihx
+
+
+
+%.rel: %.c
+	$(SDCC) $(SDCCOPTS) $(PRGOPTS) $(SDCCREV) -DFOSC=$(FOSC) -o $@ -c $<
+
+
+
+eeprom:
+	sed -ne '/:..1/ { s/1/0/2; p }' main.hex > eeprom.hex
+
+flash: $(FLASHFILE)
+	$(STCGAL) -p $(STCGALPORT) -P $(STCGALPROT) -t $(SYSCLK) $(STCGALOPTS) $(FLASHFILE)
+
+clean:
+	rm -f *.obj
+	rm -f *.ihx *.hex *.bin *.rst
+	rm -f *.map
+	rm -f *.rel
+	rm -f *.lst
+	rm -f *.sym
+	rm -f *.lk
+	rm -f *.mem
+	rm -f *.lib
+	rm -f *.asm
+
+cpp: SDCCOPTS+=-E
+cpp: main
diff --git a/README.md b/README.md
index 8badbcd..7c064da 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,4 @@
 # calc8051
 
+git submodule update --init --recursive
+
diff --git a/calc.c b/calc.c
new file mode 100644
index 0000000..99113e0
--- /dev/null
+++ b/calc.c
@@ -0,0 +1,90 @@
+
+#include "mc8051fun/mc8051fun.h"
+#include "mc8051fun/lcd.h"
+
+#define NBYTES 8
+#define BCDBYTES (NBYTES+NBYTES/2)
+
+__xdata uint8_t val0[NBYTES];
+__xdata uint8_t val1[NBYTES];
+__xdata uint8_t result[NBYTES];
+__xdata uint8_t rest[NBYTES];
+__xdata uint8_t bcd[BCDBYTES];
+
+
+static void init (void)
+{
+	lcd_cmd(LCD_SET_FUNCTION | LCD_FUNCTION_8BIT | LCD_FUNCTION_2LINE);
+	lcd_cmd(LCD_SET_DISPLAY | LCD_DISPLAY_ON);
+	lcd_cmd(LCD_CLEAR_DISPLAY);
+	lcd_cmd(LCD_SET_DDADR);
+}
+
+static void putchar(char c)
+{
+	lcd_chr(c);
+}
+static void lcd_str (char *p)
+{
+	while(*p){
+		putchar(*p++);
+	}
+}
+
+static void zero_val(__xdata uint8_t * ptr)
+{
+	for(int i=0; i<NBYTES; i++){
+		ptr[i]=0;
+	}
+}
+
+static void val0tobcd()
+{
+	__asm
+	mov	r7,#NBYTES
+	mov	r6,#BCDBYTES
+	mov	r0,#_val0
+	mov	r1,#_bcd
+	acall	long_xtobcd
+	__endasm;
+}
+
+static void printbcdval()
+{
+	uint8_t b;
+	for(int i=BCDBYTES-6; i>=0; i--){
+		b=bcd[i]>>4;
+		putchar(b+0x30);
+		b=bcd[i]&0xf;
+		putchar(b+0x30);
+	}
+}
+
+static void val0val1_add()
+{
+	__asm
+	mov	r0,#_val0
+	mov	r1,#_val1
+	mov	r7,#NBYTES
+	lcall	long_xadd
+	__endasm;
+
+}
+
+
+void main()
+{
+	init();
+	zero_val(val0);
+	zero_val(val1);
+
+	val1[0]=0x01;
+	lcd_str("Hello World!");
+	while(1){
+		val0val1_add();
+		val0tobcd();
+
+		lcd_cmd(LCD_GOTO_LINE2);
+		printbcdval();
+	}
+}
diff --git a/mc8051fun b/mc8051fun
new file mode 160000
index 0000000..9a906c3
--- /dev/null
+++ b/mc8051fun
@@ -0,0 +1 @@
+Subproject commit 9a906c35ad0974b1e3f9b34468a87a4b0e46dd51