safer reset routine for MEGA65

src/kernal/board_m65/mega65_imports.s

@@ -41,6 +41,7 @@
 .label viciv_hotregs_on                = KERNAL_0.viciv_hotregs_on
 .label viciv_hotregs_off               = KERNAL_0.viciv_hotregs_off
 
+.label m65_clr_magictstr               = KERNAL_0.m65_clr_magictstr
 .label m65_scrtab_txtwidth             = KERNAL_0.m65_scrtab_txtwidth
 .label m65_scrtab_txtheight            = KERNAL_0.m65_scrtab_txtheight
 .label m65_screen_set_indx             = KERNAL_0.m65_screen_set_indx

src/kernal/board_m65/mega65_reset_part.s

@@ -0,0 +1,26 @@
+// #LAYOUT# M65 KERNAL_0 #TAKE
+// #LAYOUT# *   *        #IGNORE
+
+// MEGA65 specific part of the hardware
+
+
+m65_reset_part:
+
+	jsr map_NORMAL           // we want normal memory mapping
+	jsr viciv_shutdown       // by default we do not want the VIC-IV
+
+	jsr M65_MODEGET
+	bcs !+
+
+	// Clear MEAGA65 native mode mark, it might cause confusion
+	
+m65_clr_magictstr: // entry point for mode switching routine
+
+	lda #$00
+	sta M65_MAGICSTR+0
+	sta M65_MAGICSTR+1
+	sta M65_MAGICSTR+2
+
+	// FALLTROUGH
+!:
+	rts

src/kernal/extapi_m65/mega65_modeset.s

@@ -18,10 +18,7 @@ m65_mode64:
 
 	// Set the magic string to mark legacy mode
 
-	lda #$00
+	jsr m65_clr_magictstr
-	sta M65_MAGICSTR+0
-	sta M65_MAGICSTR+1
-	sta M65_MAGICSTR+2
 
 	// Restore VIC-II configuration
 

src/kernal/init/fce2.hw_entry_reset.s

@@ -27,8 +27,7 @@ hw_entry_reset:
 
 #if ROM_LAYOUT_M65
 
-	jsr map_NORMAL           // we want normal memory mapping
+	jsr m65_reset_part
-	jsr viciv_shutdown       // by default we do not want the VIC-IV
 
 #endif
 
@@ -62,7 +61,7 @@ hw_entry_reset:
 	// also affirmed by c64 prg p269
 	jsr JRESTOR
 
-	//  "Compute's Mapping the 64" p236
+	// "Compute's Mapping the 64" p236
 	jsr JCINT
 
 #if ROM_LAYOUT_M65