more work towards MEGA65 native mode screen support

src/kernal/screen_m65/mega65_chrout_screen.s

@@ -1,9 +1,40 @@
 // #LAYOUT# M65 KERNAL_1 #TAKE
 // #LAYOUT# *   *        #IGNORE
 
+//
+// CHROUT routine - screen support (character output), MEGA65 native mode version
+//
+
 
 m65_chrout_screen:
 
-	// XXX provide implementation
+	// XXX hide cursor if visible
+
+	lda SCHAR
+	tax
+
+	// All the PETSCII control codes are within $0x, $1x, $8x, $9x, remaining
+	// ones are always printable characters; separate away control codes
+
+	and #$60
+	beq_16 m65_chrout_screen_control
+	txa
+
+	// Literals - first convert PETSCII to screen code
+
+	jsr chrout_to_screen_code
+
+	// FALLTROUGH
+
+m65_chrout_screen_literal: // entry point for m65_chrout_screen_quote
+
+	// Write normal character on the screen
+
+	tax                                // store screen code, we need .A for calculations
+
+	// XXX continue the implementation
+
+
+
 
 	rts

src/kernal/screen_m65/mega65_chrout_screen_control.s

@@ -0,0 +1,9 @@
+// #LAYOUT# M65 KERNAL_1 #TAKE
+// #LAYOUT# *   *        #IGNORE
+
+
+m65_chrout_screen_control:
+
+	// XXX provide implementation
+
+	rts

src/kernal/screen_m65/mega65_clrscr.s

@@ -113,6 +113,10 @@ m65_clrscr_loop:
 
     // Set screen variables
 
-	// XXX implement this, together with HOME
+	// XXX provide proper implementation, together with HOME
+
+	lda #$00
+	sta M65__TXTROW
+	sta M65__TXTCOL
 
 	rts