more error return routines in Kernal

c64/kernal/errors.s

@@ -1,6 +1,53 @@
 
+;; Kernal error codes are described in 'Commodore 64 Programmer's Reference Guide', page 306
+
+kernalerror_common:
+	sta DFLTN
+	sec
+	rts
+
+kernalerror_ROUTINE_TERMINATED: ; by a STOP key
+	lda #$00
+	jmp kernalerror_common
+
+kernalerror_TOO_MANY_OPEN_FILES:
+	lda #$01
+	jmp kernalerror_common
+
+kernalerror_FILE_ALREADY_OPEN:
+	lda #$02
+	jmp kernalerror_common
+
+kernalerror_FILE_NOT_OPEN:
+	lda #$03
+	jmp kernalerror_common
+
+kernalerror_FILE_NOT_FOUND:
+	lda #$04
+	jmp kernalerror_common
 
 kernalerror_DEVICE_NOT_FOUND:
 	lda #$05
+	jmp kernalerror_common
+
+kernalerror_FILE_NOT_INPUT:
+	lda #$06
+	jmp kernalerror_common
+
+kernalerror_FILE_NOT_OUTPUT:
+	lda #$07
+	jmp kernalerror_common
+
+kernalerror_FILE_NAME_MISSING:
+	lda #$08
+	jmp kernalerror_common
+	
+kernalerror_ILLEGAL_DEVICE_NUMBER:
+	lda #$09
+	jmp kernalerror_common
+
+kernalerror_TOP_MEM_RS232:
+	lda #$F0
+	sta RSSTAT
 	sec
 	rts