diff --git a/include/mISDN/mISDNif.h b/include/mISDN/mISDNif.h
index 4b39b83..ad9a8fe 100644
--- a/include/mISDN/mISDNif.h
+++ b/include/mISDN/mISDNif.h
@@ -38,7 +38,7 @@
  */
 #define	MISDN_MAJOR_VERSION	1
 #define	MISDN_MINOR_VERSION	1
-#define MISDN_RELEASE		22
+#define MISDN_RELEASE		24
 
 /* primitives for information exchange
  * generell format
@@ -230,7 +230,7 @@
 
 #define ISDN_P_B_MASK		0x1f
 #define ISDN_P_B_START		0x20
-
+#define ISDN_P_B_PCM		0x20
 #define ISDN_P_B_RAW		0x21
 #define ISDN_P_B_HDLC		0x22
 #define ISDN_P_B_X75SLP		0x23
@@ -361,8 +361,8 @@ clear_channelmap(u_int nr, u_char *map)
 #define MISDN_CTRL_LOOP			0x0001
 #define MISDN_CTRL_CONNECT		0x0002
 #define MISDN_CTRL_DISCONNECT		0x0004
-#define MISDN_CTRL_PCMCONNECT		0x0010
-#define MISDN_CTRL_PCMDISCONNECT	0x0020
+#define MISDN_CTRL_GET_PCM_SLOTS	0x0010
+#define MISDN_CTRL_SET_PCM_SLOTS	0x0020
 #define MISDN_CTRL_SETPEER		0x0040
 #define MISDN_CTRL_UNSETPEER		0x0080
 #define MISDN_CTRL_RX_OFF		0x0100
@@ -379,7 +379,12 @@ clear_channelmap(u_int nr, u_char *map)
 #define MISDN_CTRL_HFC_RECEIVE_ON	0x4006
 #define MISDN_CTRL_HFC_ECHOCAN_ON 	0x4007
 #define MISDN_CTRL_HFC_ECHOCAN_OFF 	0x4008
+#define MISDN_CTRL_HFC_WD_INIT		0x4009
+#define MISDN_CTRL_HFC_WD_RESET		0x400A
 
+/* special PCM slot numbers */
+#define MISDN_PCM_SLOT_DISABLE	-1	/* PCM disabled */
+#define MISDN_PCM_SLOT_IGNORE	-2	/* PCM setting will be not changed */
 
 /* socket options */
 #define MISDN_TIME_STAMP		0x0001
@@ -389,6 +394,7 @@ struct mISDN_ctrl_req {
 	int		channel;
 	int		p1;
 	int		p2;
+	int		p3;
 };
 
 /* muxer options */
diff --git a/include/mISDN/mlayer3.h b/include/mISDN/mlayer3.h
index 893a16c..ad41f90 100644
--- a/include/mISDN/mlayer3.h
+++ b/include/mISDN/mlayer3.h
@@ -22,7 +22,6 @@
 extern "C" {
 #endif
 
-
 struct l3_head {
 	unsigned char	type;
 	unsigned char	crlen;
@@ -91,13 +90,24 @@ struct mlayer3;
  */
 typedef int (mlayer3_cb_t)(struct mlayer3 *, unsigned int, unsigned int, struct l3_msg *);
 
+
+/*
+ * To avoid to include always all headers needed for mISDNif.h we redefine MISDN_CHMAP_SIZE here
+ * Please make sure to keep it in sync with mISDNif.h (but changes are very unlikely)
+ */
+#ifndef MISDN_CHMAP_SIZE
+#define MISDN_MAX_CHANNEL	127
+#define MISDN_CHMAP_SIZE	((MISDN_MAX_CHANNEL + 1) >> 3)
+#endif
+
 struct mlayer3 {
 	unsigned int	device;
 	unsigned int	nr_bchannel;
 	unsigned long	options;
 	mlayer3_cb_t	*to_layer3;
 	mlayer3_cb_t	*from_layer3;
-	void		*priv; /* free user for applications */
+	void		*priv; /* free use for applications */
+	unsigned char	channelmap[MISDN_CHMAP_SIZE];
 };
 
 /*
@@ -129,6 +139,7 @@ struct mlayer3 {
 #define MT_FREE			0x1001
 #define MT_L2ESTABLISH		0x2000
 #define MT_L2RELEASE		0x2001
+#define MT_L2IDLE		0x2002
 #define MT_ERROR		0x8000
 #define MT_TIMEOUT		0x8001
 
@@ -139,6 +150,7 @@ struct mlayer3 {
  */
 #define MISDN_PID_DUMMY		0x81000000
 #define MISDN_PID_GLOBAL	0x82000000
+#define MISDN_PID_NONE		0xFFFFFFFF
 #define MISDN_PID_MASTER	0xFF000000
 #define MISDN_PID_CRTYPE_MASK	0xFF000000
 #define MISDN_PID_CID_MASK	0x00FF0000
@@ -162,11 +174,11 @@ extern void             cleanup_layer3(void);
 
 /*
  * open a layer3 stack
- * parameter1 - device id
- * parameter2 - protocol
- * parameter3 - layer3 additional properties
- * parameter4 - callback function to deliver messages
- * parameter5 - pointer for private application use
+ * @parameter1 - device id
+ * @parameter2 - protocol
+ * @parameter3 - layer3 additional properties
+ * @parameter4 - callback function to deliver messages
+ * @parameter5 - pointer for private application use
  */
 extern struct mlayer3	*open_layer3(unsigned int, unsigned int, unsigned int, mlayer3_cb_t *, void *);
 
@@ -177,6 +189,8 @@ extern struct mlayer3	*open_layer3(unsigned int, unsigned int, unsigned int, mla
 extern void		close_layer3(struct mlayer3 *);
 
 extern unsigned int	request_new_pid(struct mlayer3 *);
+extern int		mISDN_get_pcm_slots(struct mlayer3 *, int, int *, int *);
+extern int		mISDN_set_pcm_slots(struct mlayer3 *, int, int, int);
 extern struct l3_msg	*alloc_l3_msg(void);
 extern void		free_l3_msg(struct l3_msg *);
 extern int		add_layer3_ie(struct l3_msg *, unsigned char, int, unsigned char *);
diff --git a/lib/mlayer3.c b/lib/mlayer3.c
index 8274c01..1b2c071 100644
--- a/lib/mlayer3.c
+++ b/lib/mlayer3.c
@@ -110,6 +110,7 @@ open_layer3(unsigned int dev, unsigned int proto, unsigned int prop, mlayer3_cb_
 	}
 	close(fd);
 	l3->ml3.nr_bchannel = devinfo.nrbchan;
+	memcpy(l3->ml3.channelmap, devinfo.channelmap, MISDN_CHMAP_SIZE);
 	if (!(devinfo.Dprotocols & (1 << ISDN_P_TE_E1))
 	 && !(devinfo.Dprotocols & (1 << ISDN_P_NT_E1)))
 		test_and_set_bit(FLG_BASICRATE, &l3->ml3.options);
@@ -219,3 +220,44 @@ close_layer3(struct mlayer3 *ml3)
 	free(l3);
 }
 
+int
+mISDN_set_pcm_slots(struct mlayer3 *ml3, int channel, int tx, int rx)
+{
+	struct _layer3	*l3;
+	struct mISDN_ctrl_req ctrlrq;
+	int ret;
+
+	ctrlrq.op = MISDN_CTRL_SET_PCM_SLOTS;
+	ctrlrq.channel = 0; /* via D-channel */
+	ctrlrq.p1 = channel;
+	ctrlrq.p2 = tx;
+	ctrlrq.p3 = rx;
+	l3 = container_of(ml3, struct _layer3, ml3);
+	ret = ioctl(l3->l2sock, IMCTRLREQ, &ctrlrq);
+	if (ret < 0)
+		fprintf(stderr, "could not send IOCTL IMCTRLREQ %s\n", strerror(errno));
+	return ret;
+}
+
+int
+mISDN_get_pcm_slots(struct mlayer3 *ml3, int channel, int *txp, int *rxp)
+{
+	struct _layer3	*l3;
+	struct mISDN_ctrl_req ctrlrq;
+	int ret;
+
+	ctrlrq.op = MISDN_CTRL_GET_PCM_SLOTS;
+	ctrlrq.channel = 0; /* via D-channel */
+	ctrlrq.p1 = channel;
+	l3 = container_of(ml3, struct _layer3, ml3);
+	ret = ioctl(l3->l2sock, IMCTRLREQ, &ctrlrq);
+	if (ret < 0)
+		fprintf(stderr, "could not send IOCTL IMCTRLREQ %s\n", strerror(errno));
+	else {
+		if (txp)
+			*txp = ctrlrq.p2;
+		if (rxp)
+			*rxp = ctrlrq.p3;
+	}
+	return ret;
+}