implemented WAIT command

src/basic/basic_commands/cmd__unimplemented.s

@@ -27,8 +27,6 @@ cmd_return:
 	+nop
 cmd_on:
 	+nop
-cmd_wait:
-	+nop
 cmd_def:
 	+nop
 cmd_printhash:

src/basic/basic_commands/cmd_poke.s

@@ -5,7 +5,6 @@
 
 cmd_poke:
 
-
 	; Fetch address, store it on the stack
 
 	jsr fetch_uint16

src/basic/basic_commands/cmd_wait.s

@@ -0,0 +1,62 @@
+;; #LAYOUT# STD *       #TAKE
+;; #LAYOUT# *   BASIC_0 #TAKE
+;; #LAYOUT# *   *       #IGNORE
+
+
+cmd_wait:
+
+	; Fetch address, store it on the stack
+
+	jsr fetch_uint16
+	+bcs do_SYNTAX_error
+
+	lda LINNUM+0
+	pha
+	lda LINNUM+1
+	pha
+
+	; Fetch 1st value, store it on the stack
+
+	jsr fetch_coma_uint8
+	+bcs do_SYNTAX_error
+	pha
+
+	; Fetch 2nd value
+
+	jsr fetch_coma_uint8
+	bcc @1
+	lda #$00
+@1:
+
+	; Put all the values into work area
+
+	sta INDEX+3
+	pla
+	sta INDEX+2
+	pla
+	sta INDEX+1
+	pla
+	sta INDEX+0
+
+!ifdef CONFIG_MB_M65 {
+
+	jsr helper_eggshell
+}
+
+	ldy #$00
+	; FALLTROUGH
+
+cmd_wait_loop:
+
+	; Wait for the congition to be met - see https://www.c64-wiki.com/wiki/WAIT
+
+	lda (INDEX), y
+	eor INDEX+3
+	and INDEX+2
+	beq cmd_wait_loop
+
+	; FALLTROUGH
+
+cmd_wait_end:
+
+	rts

src/basic/basic_commands/helper_eggshell_m65.s

@@ -0,0 +1,19 @@
+;; #LAYOUT# M65 BASIC_0 #TAKE
+;; #LAYOUT# M65 BASIC_1 #TAKE
+;; #LAYOUT# *   *       #IGNORE
+
+
+helper_eggshell:
+
+!ifdef SEGMENT_M65_BASIC_0 {
+
+	jsr map_BASIC_1
+	jsr (VB1__helper_eggshell)
+	jmp map_NORMAL
+
+} else {
+
+	; XXX implement till Easter
+
+	rts
+}