diff --git a/feedback/firmware/Makefile b/feedback/firmware/Makefile
new file mode 100644
index 0000000..7225ebd
--- /dev/null
+++ b/feedback/firmware/Makefile
@@ -0,0 +1,115 @@
+PRG            = feedback
+AVRCANLIB_PATH = ../../avr-can-lib
+OBJ            = main.o \
+	$(AVRCANLIB_PATH)/src/at90can_buffer.o \
+	$(AVRCANLIB_PATH)/src/at90can.o \
+	$(AVRCANLIB_PATH)/src/at90can_disable_dyn_filter.o \
+	$(AVRCANLIB_PATH)/src/at90can_error_register.o \
+	$(AVRCANLIB_PATH)/src/at90can_get_buf_message.o \
+	$(AVRCANLIB_PATH)/src/at90can_get_dyn_filter.o \
+	$(AVRCANLIB_PATH)/src/at90can_get_message.o \
+	$(AVRCANLIB_PATH)/src/at90can_send_buf_message.o \
+	$(AVRCANLIB_PATH)/src/at90can_send_message.o \
+	$(AVRCANLIB_PATH)/src/at90can_set_dyn_filter.o \
+	$(AVRCANLIB_PATH)/src/at90can_set_mode.o \
+	$(AVRCANLIB_PATH)/src/can_buffer.o
+# These were defined for the avr-can-lib, but they really, really
+# shouldn't be used there because they affect the whole program.
+OPTIMIZE       = -Os -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums
+PROGRAMMER     = usbtiny
+
+MCU_TARGET     = atmega32m1
+DEFS           = -DF_CPU=16000000UL -DHAS_CAN_CONFIG_H
+
+INCLUDES       = -I. -I$(AVRCANLIB_PATH)
+LIBS           =
+
+LFUSE          = 0xdf
+HFUSE          = 0xd9
+EFUSE          = 0xfe
+
+EXTRA_CLEAN_FILES =
+
+# You should not have to change anything below here.
+
+CC             = avr-gcc
+DUDE           = avrdude
+
+HOST_CC        = gcc
+HOST_CFLAGS    = -O0 -g
+HOST_LDFLAGS   = 
+
+# Override is only needed by avr-lib build system.
+
+override CFLAGS        = -g -Wall $(OPTIMIZE) -mmcu=$(MCU_TARGET) $(DEFS) $(INCLUDES)
+override LDFLAGS       = -Wl,-Map,$(PRG).map
+
+DUDEFLAGS      = -c $(PROGRAMMER) -p $(MCU_TARGET)
+
+OBJCOPY        = avr-objcopy
+OBJDUMP        = avr-objdump
+
+all: $(PRG).elf lst text eeprom
+
+$(PRG).elf: $(OBJ) $(LIBS)
+	$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $^ $(LIBS)
+
+clean:
+	rm -f $(OBJ) $(PRG).elf $(PRG).lst $(PRG).map $(PRG).bin $(PRG).hex $(PRG).srec $(PRG)_eeprom.bin $(PRG)_eeprom.hex $(PRG)_eeprom.srec $(EXTRA_CLEAN_FILES)
+
+lst:  $(PRG).lst
+
+%.lst: %.elf
+	$(OBJDUMP) -h -S $< > $@
+
+# Rules for flashing, EEPROM writing and fuse bit setting
+
+flash: $(PRG).hex $(PRG)_eeprom.hex
+	$(DUDE) $(DUDEFLAGS) -U eeprom:w:$(PRG)_eeprom.hex:i -U flash:w:$(PRG).hex:i
+
+flashprg: $(PRG).hex
+	$(DUDE) $(DUDEFLAGS) -U flash:w:$(PRG).hex:i
+
+flasheep: $(PRG)_eeprom.hex
+	$(DUDE) $(DUDEFLAGS) -U eeprom:w:$(PRG)_eeprom.hex:i
+
+fuse:
+	$(DUDE) $(DUDEFLAGS) -U hfuse:w:$(HFUSE):m -U lfuse:w:$(LFUSE):m -U efuse:w:$(EFUSE):m
+
+# Rules for building the .text rom images
+
+text: hex bin srec
+
+hex:  $(PRG).hex
+bin:  $(PRG).bin
+srec: $(PRG).srec
+
+%.hex: %.elf
+	$(OBJCOPY) -j .text -j .data -O ihex $< $@
+
+%.srec: %.elf
+	$(OBJCOPY) -j .text -j .data -O srec $< $@
+
+%.bin: %.elf
+	$(OBJCOPY) -j .text -j .data -O binary $< $@
+
+# Rules for building the .eeprom rom images
+
+eeprom: ehex ebin esrec
+
+ehex:  $(PRG)_eeprom.hex
+ebin:  $(PRG)_eeprom.bin
+esrec: $(PRG)_eeprom.srec
+
+%_eeprom.hex: %.elf
+	$(OBJCOPY) -j .eeprom --change-section-lma .eeprom=0 -O ihex $< $@ \
+	|| { echo empty $@ not generated; exit 0; }
+
+%_eeprom.srec: %.elf
+	$(OBJCOPY) -j .eeprom --change-section-lma .eeprom=0 -O srec $< $@ \
+	|| { echo empty $@ not generated; exit 0; }
+
+%_eeprom.bin: %.elf
+	$(OBJCOPY) -j .eeprom --change-section-lma .eeprom=0 -O binary $< $@ \
+	|| { echo empty $@ not generated; exit 0; }
+
diff --git a/feedback/firmware/can_config.h b/feedback/firmware/can_config.h
new file mode 100644
index 0000000..547b9db
--- /dev/null
+++ b/feedback/firmware/can_config.h
@@ -0,0 +1,79 @@
+#ifndef	CONFIG_H
+#define	CONFIG_H
+
+#define CAN_CONFIG_LOADED
+
+// -----------------------------------------------------------------------------
+/* Global settings for building the can-lib and application program.
+ *
+ * The following two #defines must be set identically for the can-lib and
+ * your application program. They control the underlying CAN struct. If the
+ * settings disagree, the underlying CAN struct will be broken, with
+ * unpredictable results.
+ * If can.h detects that any of the #defines is not defined, it will set them
+ * to the default values shown here, so it is in your own interest to have a
+ * consistent setting. Ommiting the #defines in both can-lib and application
+ * program will apply the defaults in a consistent way too.
+ *
+ * Select if you want to use 29 bit identifiers.
+ */
+#define	SUPPORT_EXTENDED_CANID	1
+
+/* Select if you want to use timestamps.
+ * Timestamps are sourced from a register internal to the AT90CAN.
+ * Selecting them on any other controller will have no effect, they will
+ * be 0 all the time.
+ */
+#define	SUPPORT_TIMESTAMPS		0
+
+
+// -----------------------------------------------------------------------------
+/* Global settings for building the can-lib.
+ *
+ * Select ONE CAN controller for which you are building the can-lib. 
+ */
+#define	SUPPORT_MCP2515			0
+#define	SUPPORT_AT90CAN			1
+#define	SUPPORT_SJA1000			0
+
+
+// -----------------------------------------------------------------------------
+/* Setting for MCP2515
+ *
+ * Declare which pins you are using for communication.
+ * Remember NOT to use them in your application!
+ * It is a good idea to use bits from the port that carries MOSI, MISO, SCK.
+ */
+#define	MCP2515_CS				B,4
+#define	MCP2515_INT				B,2
+
+// -----------------------------------------------------------------------------
+// Setting for SJA1000
+
+#define	SJA1000_INT				E,0
+#define	SJA1000_MEMORY_MAPPED	1
+
+// memory-mapped interface
+#define	SJA1000_BASE_ADDR		0x8000		// for ATMega162
+
+/*
+// port-interface
+#define	SJA1000_WR				D,6
+#define	SJA1000_RD				D,7
+
+#define	SJA1000_ALE				E,1
+#define	SJA1000_CS				C,0
+#define	SJA1000_DATA			A
+*/
+
+// -----------------------------------------------------------------------------
+// Setting for AT90CAN
+
+// Number of CAN messages which are buffered in RAM additinally to the MObs
+#define CAN_RX_BUFFER_SIZE		16
+#define CAN_TX_BUFFER_SIZE		8
+
+// only available if CAN_TX_BUFFER_SIZE > 0
+#define CAN_FORCE_TX_ORDER		1
+
+#endif	// CONFIG_H
diff --git a/feedback/firmware/main.c b/feedback/firmware/main.c
new file mode 100644
index 0000000..f741c9d
--- /dev/null
+++ b/feedback/firmware/main.c
@@ -0,0 +1,79 @@
+#include <inttypes.h>
+#include <avr/io.h>
+#include <avr/interrupt.h>
+#include <util/delay.h>
+#include <can.h>
+
+static void init() {
+	// Set PB as input, pull-up off
+	DDRB = 0;
+	// Set PC0/4/6 as input, pull-up off
+	DDRC &= ~(_BV(DDC0) | _BV(DDC4) | _BV(DDC6));
+	
+	// Initialize CAN interface
+	can_init(BITRATE_125_KBPS);
+	// Regular receive/transmit mode
+	can_set_mode(NORMAL_MODE);
+
+	// Filter for status requests
+	can_filter_t filter = {
+		.id = 0x10,
+		.mask = 0x7ff,
+		.flags = {
+			.rtr = 1,
+			.extended = 0,
+		},
+	};
+	can_set_filter(0, &filter);
+
+	// Enable interrupts to start reception
+	sei();
+}
+
+static void send_status() {
+	// Get GPIO state
+	// PB -> invert -> Dend..Hend, Dempty..Fempty
+	uint8_t statusl = ~PINB;
+	// PC0,6,4 -> invert -> Gempty, Hempty, Reset
+	uint8_t pinc = ~PINC;
+	uint8_t gempty = (pinc & _BV(0)) ? _BV(0) : 0;
+	uint8_t hempty = (pinc & _BV(6)) ? _BV(1) : 0;
+	uint8_t swres = (pinc & _BV(4)) ? _BV(2) : 0;
+	uint8_t statush = gempty | hempty | swres;
+
+	if (can_check_free_buffer()) {
+		can_t msg = {
+			.id = 0x10,
+			.flags = {
+				.rtr = 0,
+			},
+			.length = 2,
+			.data = { statush, statusl, },
+		};
+		can_send_message(&msg);
+	}
+}
+
+static void loop() {
+	// Check for new messages
+	if (can_check_message()) {
+		can_t msg = { 0 };
+		uint8_t status = can_get_message(&msg);
+		if (status != 0) {
+			switch (msg.id) {
+			case 0x10:
+				if (msg.flags.rtr) {
+					send_status();
+				}
+			}
+		}
+	}
+}
+
+int main() {
+	init();
+	while (1) {
+		loop();
+	}
+}
+