diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..bbb2094
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,4 @@
+*.d
+*.o
+*.bin
+*.hex
diff --git a/PINOUT b/PINOUT
index 505ad66..a416e1d 100644
--- a/PINOUT
+++ b/PINOUT
@@ -1,6 +1,6 @@
 1 - VCC
 2 - PB0 - Fet 1
-3 - PB3 - Fet 2
+3 - PB1 - Fet 2
 4 - RESET
 5 - PB2 - Led 1
 6 - PA7 - Led 2
diff --git a/firmware/Makefile b/firmware/Makefile
new file mode 100644
index 0000000..672d8bb
--- /dev/null
+++ b/firmware/Makefile
@@ -0,0 +1,76 @@
+CFLAGS += -Wall -Os  -I. -mmcu=attiny24 -std=c99
+DEFINES += -DF_CPU=1e6
+
+OBJECTS = cup.o
+
+# further optimization:
+# this removes dead code and does global linker optimization
+#CFLAGS += -ffunction-sections -Wl,--gc-sections -Wl,--relax 
+#CFLAGS += --param inline-call-cost=2 
+
+COMPILE = avr-gcc $(CFLAGS) $(DEFINES)
+
+# symbolic targets:
+all:	firmware.hex
+
+.c.o:
+	$(COMPILE) -c $< -o $@
+
+.S.o:
+	$(COMPILE) -x assembler-with-cpp -c $< -o $@
+# "-x assembler-with-cpp" should not be necessary since this is the default
+# file type for the .S (with capital S) extension. However, upper case
+# characters are not always preserved on Windows. To ensure WinAVR
+# compatibility define the file type manually.
+
+.c.s:
+	$(COMPILE) -S $< -o $@
+
+flash:	all
+	avrdude -c usbasp -p t24 -U flash:w:firmware.hex
+
+fuses:
+	avrdude -c usbasp -p t24 -U lfuse:w:0x61:m # -U hfuse:w:0xf7:m # internal 8Mhz oscillator
+
+
+## what are the source dependencies
+%.d: %.c
+	@set -e; rm -f $@;  \
+	$(COMPILE) -MM $< | sed 's,\($*\)\.o[ :]*,\1.o $@ : ,g' > $@; 
+# line 1: exits if anything goes wrong
+# line 2a: gcc -MM outputs dependencies
+# line 2b: insert the %.d into dependency list
+
+#main.c:	version.h
+
+
+version.h: .svn/entries
+	export LANG=POSIX; (svn info 2>/dev/null || echo "Revision: unknown") | awk '/^Revision:/ {print "#define SVNVERSION \"" $$2 "\""};' >version.h
+
+
+clean:
+	rm -f *.o *.hex *.obj *.i *.s *.d */*.i */*.s */*.o */*.d version.h
+
+# file targets:
+firmware.bin:	$(OBJECTS)
+	$(COMPILE) -o firmware.bin $(OBJECTS)
+
+firmware.hex:	firmware.bin
+	rm -f firmware.hex firmware.eep.hex
+	avr-objcopy -j .text -j .data -O ihex firmware.bin firmware.hex
+	avr-size firmware.bin
+#	./checksize firmware.bin 8192 960
+# do the checksize script as our last action to allow successful compilation
+# on Windows with WinAVR where the Unix commands will fail.
+
+disasm:	firmware.bin
+	avr-objdump -d firmware.bin >disasm
+
+functionsize: disasm
+	python avrbuild/functionsize.py 
+
+countregs: disasm
+	python avrbuild/countregs.py 
+
+# for depends:
+-include $(OBJECTS:.o=.d)
diff --git a/firmware/cup.c b/firmware/cup.c
index a7ed9ef..de043dc 100644
--- a/firmware/cup.c
+++ b/firmware/cup.c
@@ -10,6 +10,8 @@
 #define FET0_PIN 0
 #define FET1_PIN 1
 
+#define TIMEOUT 255
+
 uint8_t led_color = 0;
 
 uint8_t setting_timeout = 0;
@@ -23,28 +25,58 @@ uint8_t heat_pwm = 0;
 uint8_t heat_on[2] = {0, 0};
 uint8_t heat_off[2] = {0, 0};
 
-ISR(timer1 overflow)
+uint8_t input_state = 0;
+uint8_t dev_state = 0;
+
+/* gray code to change lookup table, index is old state .. new state */
+int8_t state_change[16] = {0, 1, -1, 0,  -1, 0, 0, 1,  1, 0, 0, -1,  0, -1, 1, 0};
+
+ISR(TIM1_OVF_vect)
 {
+	/* timeout for displaying target temperature */
 	if(setting_timeout) {setting_timeout--;}
-	heat_pwm_cnt++;
 	
-	if(heat_pwm == heat_on[0]) {PORTB |= (1 << FET0);}
-	if(heat_pwm == heat_off[0]) {PORTB &= ~(1 << FET0);}
-	if(heat_pwm == heat_on[1]) {PORTB |= (1 << FET1);}
-	if(heat_pwm == heat_off[1]) {PORTB &= ~(1 << FET1);}
+	/* incremtening softpwm, toggling output if needed */
+	heat_pwm++;
+	if(heat_pwm == heat_on[0]) {PORTB |= (1 << FET0_PIN);}
+	if(heat_pwm == heat_off[0]) {PORTB &= ~(1 << FET0_PIN);}
+	if(heat_pwm == heat_on[1]) {PORTB |= (1 << FET1_PIN);}
+	if(heat_pwm == heat_off[1]) {PORTB &= ~(1 << FET1_PIN);}
+}
+
+ISR(PCINT0_vect)
+{
+	uint8_t new_state = (PORTA & ((1 << IMPULS1_PIN) | (1 << IMPULS0_PIN) | (1 << TAST_PIN))) >> 1;
+	uint8_t diff = new_state ^ input_state;
+	if(!diff) {return;}
+	
+	if(diff & (1 << TAST_PIN) && new_state & (1 << TAST_PIN))
+	{
+		dev_state = !dev_state;
+	}
+	
+	int8_t change = state_change[((input_state & 3) << 2) | (new_state & 3)];
+	if(change)
+	{
+		target += change;
+		setting_timeout = TIMEOUT;
+	}
+	
+	input_state = new_state;
 }
 
 void io_init(void)
 {
 	PORTA = (1 << TAST_PIN) | (1 << IMPULS1_PIN) | (1 << IMPULS0_PIN);/* enable pullups on inputs */
 	PORTB = 0;
-	DDRA = (1 << OC0B);/* led outputs ... */
-	DDRB = (1 << OC0A) | (1 << FET0_PIN) | (1 << FET1_PIN);/* ... and FET output */
+	DDRA = (1 << PA7);/* led outputs ... */
+	DDRB = (1 << PB2) | (1 << FET0_PIN) | (1 << FET1_PIN);/* ... and FET output */
+	input_state = PORTA & ((1 << IMPULS1_PIN) | (1 << IMPULS0_PIN) | (1 << TAST_PIN));
 }
 
 void led_init(void)
 {
-	TCCR0A = (1 << COM0A1) | (1 << COM0B1) | (1 << COM0B0) | (1 << WGM1) | (1 << WGM0);/* pwm enable: fast, A not inverted, B inverted */
+	TCCR0A = (1 << COM0A1) | (1 << COM0B1) | (1 << COM0B0) | (1 << WGM01) | (1 << WGM00);/* pwm enable: fast, A not inverted, B inverted */
 	TCCR0B = (1 << CS02) | (1 << CS00);/* prescaler / 1024 */
 	OCR0A = OCR0B = led_color;
 }
@@ -65,7 +97,7 @@ void adc_init(void)
 
 void heat_init(void)
 {
-	TCCRB1 = (1 << CS12) | (1 << CS10);/* prescaler / 1024 */
+	TCCR1B = (1 << CS12) | (1 << CS10);/* prescaler / 1024 */
 	TIMSK1 = (1 << TOIE1);/* interupt on overflow */
 	/* insert loading of heat setting here */
 }
@@ -92,8 +124,8 @@ int main(void)
 		{
 			/* new adc result */
 			ADCSRA |= (1 << ADIF);
-			adc_sum[adc_pos++] += ADC;
-			if(!adc_pos)
+			adc_sum += ADC;
+			if(!++adc_pos)
 			{
 				temp = adc_sum;
 			}