fixed DOS memory mapping

src/dos_m65/4000.dos_vectable.s

@@ -2,7 +2,7 @@
 // A vector table to integrate DOS with the MEGA65 Kernal
 
 .word dos_INIT
-.word dos_HASUNIT
+.word dos_CHKUNIT
 .word dos_ACPTR
 .word dos_CIOUT
 .word dos_LISTEN
@@ -11,30 +11,3 @@
 .word dos_TKSA
 .word dos_UNTLK
 .word dos_UNLSN
-
-
-// Dummy implementations - XXX to be replaced with real ones
-
-dos_INIT:
-	nop
-dos_HASUNIT:
-	nop
-dos_ACPTR:
-	nop
-dos_CIOUT:
-	nop
-dos_LISTEN:
-	nop
-dos_SECOND:
-	nop
-dos_TALK:
-	nop
-dos_TKSA:
-	nop
-dos_UNTLK:
-	nop
-dos_UNLSN:
-	nop
-
-	sec
-	rts

src/dos_m65/stubs.s

@@ -0,0 +1,26 @@
+
+// Dummy implementations - XXX to be replaced with real ones
+
+dos_INIT:
+	nop
+dos_CHKUNIT:
+	nop
+dos_ACPTR:
+	nop
+dos_CIOUT:
+	nop
+dos_LISTEN:
+	nop
+dos_SECOND:
+	nop
+dos_TALK:
+	nop
+dos_TKSA:
+	nop
+dos_UNTLK:
+	nop
+dos_UNLSN:
+	nop
+
+	sec
+	rts