Complete redesign of the CBM610 support.

Use wrappers to call the kernal in bank 15 instead of implementing kernal
functionality within the cc65 libs (eats performance but is much smaller and
simpler).
Improved startup/shutdown code allows a return to the system bank without
calling the BASIC cold start vector.


git-svn-id: svn://svn.cc65.org/cc65/trunk@2793 b7a2c559-68d2-44c3-8de9-860c34a00d81

libsrc/cbm610/kopen.s

@@ -0,0 +1,22 @@
+;
+; Ullrich von Bassewitz, 2003-12-20
+;
+; OPEN kernal call.
+;
+; NOTE: The OPEN system call in the CBM610 kernal is different from the 
+; standard. It evaluates the carry flag and does a normal open if carry clear
+; and some strange things (output sa 15 + name on IEC) if carry set. To be
+; compatible with our CBM file stuff, we have to clear the carry before 
+; calling the real OPEN.
+
+        .export         OPEN
+
+.proc   OPEN
+
+        clc
+        jmp     $FFC0
+
+.endproc
+
+
+