diff --git a/extruder/extruder.c b/extruder/extruder.c
index 6e97cd0..8200e48 100644
--- a/extruder/extruder.c
+++ b/extruder/extruder.c
@@ -202,13 +202,33 @@ int main (void)
 		// check if we've had a new intercom packet
 		if (intercom_flags & FLAG_NEW_RX) {
 			intercom_flags &= ~FLAG_NEW_RX;
-			
-			send_temperature(0, temp_get(0));
-			send_temperature(1, temp_get(1));
-			temp_set(0, read_temperature(0));
-			temp_set(1, read_temperature(1));
-			
-			start_send();
+
+			switch (rx.packet.control_word) {
+				// M105- read temperatures
+				case 105:
+					send_temperature(0, temp_get(0));
+					temp_set(0, read_temperature(0));
+					send_temperature(1, temp_get(1));
+					temp_set(1, read_temperature(1));
+					start_send();
+					break;
+				// M130 - set PID P factor
+				case 130:
+					pid_set_p(rx.packet.control_index, rx.packet.control_data_int32);
+				// M131 - set PID I factor
+				case 131:
+					pid_set_i(rx.packet.control_index, rx.packet.control_data_int32);
+				// M132 - set PID D factor
+				case 132:
+					pid_set_d(rx.packet.control_index, rx.packet.control_data_int32);
+				// M133 - set PID I limit
+				case 133:
+					pid_set_i_limit(rx.packet.control_index, rx.packet.control_data_int32);
+				// M134 - save PID values to eeprom
+				case 134:
+					heater_save_settings();
+					break;
+			}
 		}
 	}
 }
diff --git a/extruder/intercom.c b/extruder/intercom.c
index bf89ece..ec02cac 100644
--- a/extruder/intercom.c
+++ b/extruder/intercom.c
@@ -11,31 +11,6 @@
 
 #define	START	0x55
 
-enum {
-	ERROR_BAD_CRC
-} err_codes;
-
-typedef struct {
-	uint8_t		start;
-	uint8_t		dio;
-	uint8_t		controller_num;
-	uint8_t		control_word;
-	uint8_t		control_index;
-	union {
-		int32_t		control_data_int32;
-		uint32_t	control_data_uint32;
-		float			control_data_float;
-		uint16_t	temp[2];
-	};
-	uint8_t		err;
-	uint8_t		crc;
-} intercom_packet_t;
-
-typedef union {
-	intercom_packet_t packet;
-	uint8_t						data[sizeof(intercom_packet_t)];
-} intercom_packet;
-
 intercom_packet tx;		// this packet will be send
 intercom_packet rx;		// the last received packet with correct checksum
 intercom_packet _tx;	// current packet in transmission
diff --git a/extruder/intercom.h b/extruder/intercom.h
index 0e826fe..988ccdc 100644
--- a/extruder/intercom.h
+++ b/extruder/intercom.h
@@ -12,6 +12,34 @@
 	#define disable_transmit()			do { WRITE(TX_ENABLE_PIN,0);  UCSR0B &= ~(MASK(TXCIE0) | MASK(UDRIE0)); UCSR0B |= MASK(RXEN0); } while(0)
 #endif
 
+enum {
+	ERROR_BAD_CRC
+} err_codes;
+
+typedef struct {
+	uint8_t		start;
+	uint8_t		dio;
+	uint8_t		controller_num;
+	uint8_t		control_word;
+	uint8_t		control_index;
+	union {
+		int32_t		control_data_int32;
+		uint32_t	control_data_uint32;
+		float			control_data_float;
+		uint16_t	temp[2];
+	};
+	uint8_t		err;
+	uint8_t		crc;
+} intercom_packet_t;
+
+typedef union {
+	intercom_packet_t packet;
+	uint8_t						data[sizeof(intercom_packet_t)];
+} intercom_packet;
+
+extern intercom_packet tx;
+extern intercom_packet rx;
+
 // initialise serial subsystem
 void intercom_init(void);
 
@@ -47,4 +75,6 @@ void start_send(void);
 #define	FLAG_TX_FINISHED		8
 extern volatile uint8_t	intercom_flags;
 
+
+
 #endif	/* _INTERCOM_H */
diff --git a/intercom.c b/intercom.c
index bf89ece..ec02cac 100644
--- a/intercom.c
+++ b/intercom.c
@@ -11,31 +11,6 @@
 
 #define	START	0x55
 
-enum {
-	ERROR_BAD_CRC
-} err_codes;
-
-typedef struct {
-	uint8_t		start;
-	uint8_t		dio;
-	uint8_t		controller_num;
-	uint8_t		control_word;
-	uint8_t		control_index;
-	union {
-		int32_t		control_data_int32;
-		uint32_t	control_data_uint32;
-		float			control_data_float;
-		uint16_t	temp[2];
-	};
-	uint8_t		err;
-	uint8_t		crc;
-} intercom_packet_t;
-
-typedef union {
-	intercom_packet_t packet;
-	uint8_t						data[sizeof(intercom_packet_t)];
-} intercom_packet;
-
 intercom_packet tx;		// this packet will be send
 intercom_packet rx;		// the last received packet with correct checksum
 intercom_packet _tx;	// current packet in transmission
diff --git a/intercom.h b/intercom.h
index 0e826fe..988ccdc 100644
--- a/intercom.h
+++ b/intercom.h
@@ -12,6 +12,34 @@
 	#define disable_transmit()			do { WRITE(TX_ENABLE_PIN,0);  UCSR0B &= ~(MASK(TXCIE0) | MASK(UDRIE0)); UCSR0B |= MASK(RXEN0); } while(0)
 #endif
 
+enum {
+	ERROR_BAD_CRC
+} err_codes;
+
+typedef struct {
+	uint8_t		start;
+	uint8_t		dio;
+	uint8_t		controller_num;
+	uint8_t		control_word;
+	uint8_t		control_index;
+	union {
+		int32_t		control_data_int32;
+		uint32_t	control_data_uint32;
+		float			control_data_float;
+		uint16_t	temp[2];
+	};
+	uint8_t		err;
+	uint8_t		crc;
+} intercom_packet_t;
+
+typedef union {
+	intercom_packet_t packet;
+	uint8_t						data[sizeof(intercom_packet_t)];
+} intercom_packet;
+
+extern intercom_packet tx;
+extern intercom_packet rx;
+
 // initialise serial subsystem
 void intercom_init(void);
 
@@ -47,4 +75,6 @@ void start_send(void);
 #define	FLAG_TX_FINISHED		8
 extern volatile uint8_t	intercom_flags;
 
+
+
 #endif	/* _INTERCOM_H */