started work on setting text mode

src/kernal/extapi_m65/mega65_mode64.s

@@ -0,0 +1,26 @@
+// #LAYOUT# M65 KERNAL_1 #TAKE
+// #LAYOUT# *   *        #IGNORE
+
+
+M65_MODE64:
+
+	// Disable interrupts, they might interfere
+
+	sei
+
+	// XXX provide full implementation
+
+	// Set the magic string to mark legacy mode
+
+	lda #$00
+	sta M65_MAGICSTR+0
+	sta M65_MAGICSTR+1
+	sta M65_MAGICSTR+2
+
+	// Reenable interrupts
+
+	cli
+
+	// Switch CPU speed back to slow and quit
+
+	jmp M65_SLOW