diff --git a/bts/BTS_Tests.cfg b/bts/BTS_Tests.cfg
index c6f50ad..fb78eba 100644
--- a/bts/BTS_Tests.cfg
+++ b/bts/BTS_Tests.cfg
@@ -41,3 +41,4 @@
 BTS_Tests_SMSCB.control
 BTS_Tests_LAPDm.control
 BTS_Tests_VAMOS.control
+BTS_Tests_ASCI.control
diff --git a/bts/BTS_Tests.ttcn b/bts/BTS_Tests.ttcn
index 37d15b8..d893601 100644
--- a/bts/BTS_Tests.ttcn
+++ b/bts/BTS_Tests.ttcn
@@ -74,6 +74,7 @@
 import from TELNETasp_PortType all;
 import from BTS_Tests_LAPDm all;
 
+friend module BTS_Tests_ASCI;
 friend module BTS_Tests_SMSCB;
 friend module BTS_Tests_VAMOS;
 friend module BTS_Tests_virtphy;
diff --git a/bts/BTS_Tests_ASCI.ttcn b/bts/BTS_Tests_ASCI.ttcn
new file mode 100644
index 0000000..dfab7f6
--- /dev/null
+++ b/bts/BTS_Tests_ASCI.ttcn
@@ -0,0 +1,135 @@
+module BTS_Tests_ASCI {
+
+/* ASCI Integration Tests for OsmoBTS
+ *
+ * (C) 2023 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
+ * All Rights Reserved
+ *
+ * SPDX-License-Identifier: AGPL-3.0+
+ *
+ * Authors: Harald Welte; Andreas Eversberg
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+import from Misc_Helpers all;
+import from General_Types all;
+import from Osmocom_Types all;
+import from GSM_Types all;
+import from L1CTL_PortType all;
+import from L1CTL_Types all;
+import from LAPDm_Types all;
+import from IPA_Emulation all;
+import from GSM_RR_Types all;
+import from L3_Templates all;
+
+import from MobileL3_CommonIE_Types all;
+
+import from RSL_Emulation all;
+import from RSL_Types all;
+
+import from BTS_Tests all;
+
+
+
+/* convert from boolean value to BIT1 */
+private function bool2bit1(boolean inp) return BIT1 {
+	if (inp) {
+		return '1'B;
+	} else {
+		return '0'B;
+	}
+}
+
+/* encode a VBS/VGCS call reference into it's OCT5 representation */
+private function f_enc_gcr(integer call_ref, boolean is_group_call, boolean ack_required := false)
+return OCT5
+{
+	var DescriptiveGroupOrBroadcastCallReference_V v := {
+		binaryCodingOfGroupOrBroadcastCallReference := int2bit(call_ref, 27),
+		sF := bool2bit1(is_group_call),
+		aF := bool2bit1(ack_required),
+		callPriority := '000'B,
+		cipheringInformation := '0000'B,
+		spare := '0000'B
+	}
+	return bit2oct(encvalue(v));
+}
+
+/* Send Notification command to start and stop notifying an ASCI call.
+ * When it starts, it is expected that NCH is received by MS. Also it is expected that NCH is received again.
+ * When it stops, it is expected that NCH is not received anymore. */
+testcase TC_vbs_notification() runs on test_CT
+{
+	timer T;
+
+	f_init();
+	f_init_l1ctl();
+	f_l1_tune(L1CTL);
+
+	var OCT5 gcr := f_enc_gcr(hex2int('2342'H), false, false);
+	var OCT3 chan_desc := '234266'O;
+	var octetstring notif_nch := '090620B42230000091A1330B2B2B2B2B2B2B2B2B2B2B2B'O;
+	var integer recv_count := 0;
+
+	log("Sending RSL NOTIF_CMD (start)");
+	RSL_CCHAN.send(ts_ASP_RSL_UD(ts_RSL_NOTIF_CMD_START(gcr, chan_desc)));
+
+	/* NCH must be received twice. */
+	T.start(2.0);
+	alt {
+	[] L1CTL.receive(tr_L1CTL_DATA_IND(t_RslChanNr_PCH_AGCH(0), ?, notif_nch)) {
+		log("Received matching NOTIFICATION/NCH.");
+		recv_count := recv_count + 1;
+		if (recv_count != 2) {
+			repeat;
+		}
+		T.stop;
+		}
+	[] L1CTL.receive { repeat; }
+	[] T.timeout {
+		setverdict(fail, "Timeout waiting for NCH message");
+		}
+	}
+
+	log("Sending RSL NOTIF_CMD (stop)");
+	RSL_CCHAN.send(ts_ASP_RSL_UD(ts_RSL_NOTIF_CMD_STOP(gcr)));
+
+	/* Flush pending messages and be sure that the sending of notifications has stopped. */
+	f_sleep(1.0);
+	L1CTL.clear;
+
+	/* NCH must not be received. */
+	T.start(2.0);
+	alt {
+	[] L1CTL.receive(tr_L1CTL_DATA_IND(t_RslChanNr_PCH_AGCH(0), ?, notif_nch)) {
+		T.stop;
+		setverdict(fail, "Received unexpected NOTIFICATION/NCH.");
+		}
+	[] L1CTL.receive { repeat; }
+	[] T.timeout {
+		log("Not received NOTIFICATION/NCH. (as expected)");
+		setverdict(pass);
+		}
+	}
+
+	Misc_Helpers.f_shutdown(__BFILE__, __LINE__);
+}
+
+control {
+	execute( TC_vbs_notification() );
+
+}
+
+}