more control codes for MEGA65 screen editor

src/basic/basic_commands/cmd_go_goto_run.s

@@ -37,10 +37,10 @@ cmd_go_syntax_error:
 	jsr helper_ask_if_sure
 	bcs cmd_go_rts
 	jsr M65_MODE64
-	jmp do_clr
+	jmp_8 cmd_go_switchmode_clr_banner
 !:
 	cmp #65
-	bne !+
+	bne_16 do_ILLEGAL_QUANTITY_error
 
 	// If in C64 compatibility mode - switch to native mode
 
@@ -50,9 +50,13 @@ cmd_go_syntax_error:
 	jsr helper_ask_if_sure
 	bcs cmd_go_rts
 	jsr M65_MODE65
-	jmp do_clr
-!:
-	jmp do_ILLEGAL_QUANTITY_error
+
+	// FALLTROUGH
+
+cmd_go_switchmode_clr_banner:
+
+	jsr do_clr
+	jmp INITMSG
 
 cmd_go_rts:
 

src/basic/board_m65/mega65_imports.s

@@ -24,6 +24,7 @@
 .label JCHRIN                          = KERNAL_0.JCHRIN
 .label JREADST                         = KERNAL_0.JREADST
 .label SELDEV                          = KERNAL_0.SELDEV
+.label M65_ISMODE65                    = KERNAL_0.M65_ISMODE65
 .label plot_set                        = KERNAL_0.plot_set
 .label init_oldtxt                     = BASIC_0.init_oldtxt
 .label tmpstr_free_all_reset           = BASIC_0.tmpstr_free_all_reset

src/basic/init/initmsg_real.s

@@ -123,7 +123,8 @@ initmsg_real:
 
 #if ROM_LAYOUT_M65
 
-	// XXX make it different for future Mega65 native mode
+	jsr M65_ISMODE65
+	bcc !+                             // XXX for MEGA65 native mode, display something else instead
 
 	ldx #$02
 	ldy #$21
@@ -132,6 +133,7 @@ initmsg_real:
 	lda #<text_mode_64
 	ldy #>text_mode_64
 	jsr STROUT
+!:
 
 #endif