switching from MEGA65 native mode to legacy mode works now

src/kernal/board_m65/mega65_imports.s

@@ -36,6 +36,8 @@
 .label setup_irq_timer                 = KERNAL_0.setup_irq_timer
 .label wait_x_bars                     = KERNAL_0.wait_x_bars
 .label viciv_unhide                    = KERNAL_0.viciv_unhide
+.label viciv_init                      = KERNAL_0.viciv_init
+.label viciv_shutdown                  = KERNAL_0.viciv_shutdown
 
 .label m65_scrtab_txtwidth             = KERNAL_0.m65_scrtab_txtwidth
 .label m65_scrtab_txtheight            = KERNAL_0.m65_scrtab_txtheight

src/kernal/board_m65/mega65_viciv_init.s

@@ -0,0 +1,27 @@
+// #LAYOUT# M65 KERNAL_0 #TAKE
+// #LAYOUT# *   *        #IGNORE
+
+//
+// Routine to initialize VIC-IV for entering MEGA65 native mode
+//
+
+
+viciv_init:
+
+	// Switch VIC to VIC-IV mode
+
+	jsr viciv_unhide
+
+	// Disable badlines and slow interrupt emulation
+
+	lda #$00
+	sta MISC_EMU
+
+	// Set misc VIC-IV flags
+
+	lda #%01000000  // enable C65 character set
+	sta VIC_CTRLA
+
+	// XXX enable 48 MHz mode in VIC_CTRLC
+
+	rts

src/kernal/board_m65/mega65_viciv_shutdown.s

@@ -0,0 +1,29 @@
+// #LAYOUT# M65 KERNAL_0 #TAKE
+// #LAYOUT# *   *        #IGNORE
+
+//
+// Routine to shutdown VIC-IV for leaving MEGA65 native mode
+//
+
+
+viciv_shutdown:
+
+	// Switch VIC to VIC-IV mode, temporarily
+
+	jsr viciv_unhide
+
+	// Reenable badlines and slow interrupt emulation
+
+	lda #$03
+	sta MISC_EMU
+
+	// Set misc VIC-IV flags
+
+	lda #%00000000
+	sta VIC_CTRLA  // enable C64 character set
+	sta VIC_CTRLB  // disable extended resolution and attributes
+
+	// Hide VIC-IV registers and quit
+
+	sta VIC_KEY
+	rts

src/kernal/board_m65/mega65_viciv_unhide.s

@@ -1,15 +1,11 @@
-// #LAYOUT# STD *        #TAKE
-// #LAYOUT# X16 *        #IGNORE
-// #LAYOUT# *   KERNAL_0 #TAKE
+// #LAYOUT# M65 KERNAL_0 #TAKE
 // #LAYOUT# *   *        #IGNORE
 
 //
-// Routine to unhide Mega65 extra registers
+// Routine to unhide MEGA65 extra registers
 //
 
 
-#if ROM_LAYOUT_M65
-
 viciv_unhide:
 
 	lda #$47
@@ -18,5 +14,3 @@ viciv_unhide:
 	sta VIC_KEY
 
 	rts
-
-#endif