diff --git a/asminc/telestrat.inc b/asminc/telestrat.inc
index 8e6a66bbd..71240b38b 100644
--- a/asminc/telestrat.inc
+++ b/asminc/telestrat.inc
@@ -119,13 +119,13 @@ XTEXT            = $19
 XHIRES           = $1A
 XFILLM           = $1C
 XMINMA           = $1F
-XVARS            = $24          ; only in TELEMON 3.0, in telemon 2.4, it's XNOMFI ($24)
-XFREAD           = $27          ; only in TELEMON 3.0
-XOPEN            = $30          ; only in TELEMON 3.0
+XVARS            = $24          ; only in TELEMON 3.x, in telemon 2.4, it's XNOMFI ($24)
+XFREAD           = $27          ; only in TELEMON 3.x
+XOPEN            = $30          ; only in TELEMON 3.x
 XCOSCR           = $34          ; switch off cursor
 XCSSCR           = $35          ; switch on cursor
-XCLOSE           = $3A          ; only in TELEMON 3.0 Close file
-XFWRITE          = $3B          ; only in TELEMON 3.0 write file
+XCLOSE           = $3A          ; only in TELEMON 3.x Close file
+XFWRITE          = $3B          ; only in TELEMON 3.x write file
 XSONPS           = $40
 XOUPS            = $42
 XPLAY            = $43
@@ -133,6 +133,7 @@ XSOUND           = $44
 XMUSIC           = $45 
 XZAP             = $46
 XSHOOT           = $47
+XSOUT            = $67          ; Send A register to RS232, available in telemon 2.4 & 3.x
 XCIRCL           = $8F
 XCURSE           = $90
 XPAPER           = $92