diff --git a/library/L1CTL_Types.ttcn b/library/L1CTL_Types.ttcn
index 6bfebb3..1b50703 100644
--- a/library/L1CTL_Types.ttcn
+++ b/library/L1CTL_Types.ttcn
@@ -181,7 +181,10 @@
 	type record L1ctlTchModeConf {
 		L1ctlTchMode	tch_mode,
 		L1ctlAudioMode	audio_mode,
-		OCT2		padding
+		record {
+			uint8_t	start_codec,
+			BIT8	codecs_bitmask
+		} amr
 	} with { variant "" };
 
 	type record L1ctlDataInd {
@@ -284,7 +287,10 @@
 		L1ctlTchMode	tch_mode,
 		L1ctlAudioMode	audio_mode,
 		L1ctlLoopMode	loop_mode,
-		OCT1		padding
+		record {
+			uint8_t	start_codec,
+			BIT8	codecs_bitmask
+		} amr
 	} with { variant "" };
 
 	type record L1ctlRachReq {
@@ -532,7 +538,9 @@
 	template (value) L1ctlUlMessage
 	ts_L1CTL_TCH_MODE_REQ(template (value) L1ctlTchMode tch_mode := L1CTL_CHAN_MODE_SIGN,
 			      template (value) L1ctlAudioMode audio_mode := t_L1CTL_AudioModeFwd,
-			      template (value) L1ctlLoopMode loop_mode := L1CTL_LOOP_MODE_OPEN) := {
+			      template (value) L1ctlLoopMode loop_mode := L1CTL_LOOP_MODE_OPEN,
+			      template (value) uint8_t amr_start_codec := 0,
+			      template (value) BIT8 amr_codecs_bitmask := '00000000'B) := {
 		header := ts_L1ctlHeader(L1CTL_TCH_MODE_REQ),
 		ul_info := omit,
 		ul_info_tbf := omit,
@@ -542,7 +550,10 @@
 				tch_mode := tch_mode,
 				audio_mode := audio_mode,
 				loop_mode := loop_mode,
-				padding := '00'O
+				amr := {
+					start_codec := amr_start_codec,
+					codecs_bitmask := amr_codecs_bitmask
+				}
 			}
 		}
 	};