diff --git a/compiler/src/prog8/compiler/target/cbm/Petscii.kt b/compiler/src/prog8/compiler/target/cbm/Petscii.kt
index 04dc4d325..07b98f674 100644
--- a/compiler/src/prog8/compiler/target/cbm/Petscii.kt
+++ b/compiler/src/prog8/compiler/target/cbm/Petscii.kt
@@ -1,5 +1,6 @@
 package prog8.compiler.target.cbm
 
+import prog8.ast.antlr.escape
 import java.io.CharConversionException
 
 object Petscii {
@@ -1073,7 +1074,7 @@ object Petscii {
                 }
                 else -> {
                     val case = if (lowercase) "lower" else "upper"
-                    throw CharConversionException("no ${case}Petscii character for '$chr' (${chr.code})")
+                    throw CharConversionException("no ${case}Petscii character for '${escape(chr.toString())}' (${chr.code})")
                 }
             }
         }
@@ -1110,7 +1111,7 @@ object Petscii {
                 }
                 else -> {
                     val case = if (lowercase) "lower" else "upper"
-                    throw CharConversionException("no ${case}Screencode character for '$chr' (${chr.code})")
+                    throw CharConversionException("no ${case}Screencode character for '${escape(chr.toString())}' (${chr.code})")
                 }
             }
         }
diff --git a/compilerAst/src/prog8/ast/antlr/EscapeChars.kt b/compilerAst/src/prog8/ast/antlr/EscapeChars.kt
index c3c743d1c..7752272e1 100644
--- a/compilerAst/src/prog8/ast/antlr/EscapeChars.kt
+++ b/compilerAst/src/prog8/ast/antlr/EscapeChars.kt
@@ -10,9 +10,9 @@ fun escape(str: String): String {
             '\n' -> "\\n"
             '\r' -> "\\r"
             '"' -> "\\\""
-            in '\u8000'..'\u80ff' -> "\\x" + (it.toInt() - 0x8000).toString(16).padStart(2, '0')
+            in '\u8000'..'\u80ff' -> "\\x" + (it.code - 0x8000).toString(16).padStart(2, '0')
             in '\u0000'..'\u00ff' -> it.toString()
-            else -> "\\u" + it.toInt().toString(16).padStart(4, '0')
+            else -> "\\u" + it.code.toString(16).padStart(4, '0')
         }
     }
     return es.joinToString("")
diff --git a/examples/test.p8 b/examples/test.p8
index 37a4c513c..d1109f13a 100644
--- a/examples/test.p8
+++ b/examples/test.p8
@@ -1,23 +1,27 @@
-%import textio
-%zeropage basicsafe
-%option no_sysinit
+ 	%import textio ; txt.*
+ 	main {
+ 		sub start() {
+ 			; ATTENTION: uncomment only one problematic line at a time!
 
-main {
+ 			; Normal string literals, i.e. PETSCII encoding
+ 			; ---------------------------------------------
+ 			txt.print("\"")	; fine
+ 			txt.print("\n")	; fine
+ 			txt.print("\r")	; fine
+ 			; txt.print("\\")	; yields CharConversionException
+ 			; txt.print("xyz\\")	; yields prog8.compiler.AssemblyError
 
-	byte[] xs1 = "foo1" ; <<<<<<<<<<<<
-	str xs2 = "foo2" ; <<<<<<<<<<<<
-	sub start() {
-	    txt.print(xs1)
-            stringopt()
-	}
+ 			; @-strings, i.e. translated into
+ 			; the alternate character encoding (Screencodes/pokes)
+ 			; ----------------------------------------------------
+ 			txt.print(@"\"")	; fine
+ 			txt.print(@"\n")	; yields CharConversionException
+ 			; txt.print(@"xyz\n")	; yields prog8.compiler.AssemblyError
+ 			; txt.print(@"\r")	; yields CharConversionException
+ 			; txt.print(@"xyz\r")	; yields prog8.compiler.AssemblyError
+ 			; txt.print(@"\\")	; yields CharConversionException
+ 			; txt.print(@"\\")	; yields prog8.compiler.AssemblyError
 
-        sub stringopt() {
-            str  message = "a"
-
-            txt.print(message)
-            txt.nl()
-            message[0] = '@'
-            txt.print(message)
-            txt.nl()
-        }
-}
+ 			; there may be more...
+ 		}
+ 	}