From 1497330cc06512aff6a6708ba2d9e053b38ca7e1 Mon Sep 17 00:00:00 2001
From: jede <jede@oric.org>
Date: Sat, 25 Feb 2017 22:10:13 +0100
Subject: [PATCH] adding clrscr.s

---
 asminc/telestrat.inc      |  3 +++
 libsrc/telestrat/clrscr.s | 31 +++++++++++++++++++++++++++++++
 libsrc/telestrat/gotoxy.s |  2 ++
 3 files changed, 36 insertions(+)
 create mode 100644 libsrc/telestrat/clrscr.s

diff --git a/asminc/telestrat.inc b/asminc/telestrat.inc
index ab209e520..8a51e1c32 100644
--- a/asminc/telestrat.inc
+++ b/asminc/telestrat.inc
@@ -133,6 +133,9 @@ XPING            = $9D
 ; Page $200
 SCRX             := $220
 SCRY             := $224
+ADSCRL           := $218
+ADSCRH           := $21C
+
 
 ; ---------------------------------------------------------------------------
 ; Page $500
diff --git a/libsrc/telestrat/clrscr.s b/libsrc/telestrat/clrscr.s
new file mode 100644
index 000000000..8c45aeeec
--- /dev/null
+++ b/libsrc/telestrat/clrscr.s
@@ -0,0 +1,31 @@
+    .export    _clrscr
+	
+    .importzp  sp
+	
+    .include   "telestrat.inc"
+
+.proc _clrscr
+    lda     #<SCREEN
+	ldy     #>SCREEN
+    sta     RES
+    sty     RES+1
+
+    ldy     #<(SCREEN+SCREEN_XSIZE*SCREEN_YSIZE)
+    ldx     #>(SCREEN+SCREEN_XSIZE*SCREEN_YSIZE)
+    lda     #' '
+    BRK_TELEMON XFILLM
+	
+	
+	; reset prompt position
+    lda     #<(SCREEN+40)
+    sta     ADSCRL
+    lda     #>(SCREEN+40)
+    sta     ADSCRH
+	
+	; reset display position
+	lda     #$01
+    sta     SCRY
+    lda     #$02
+    sta     SCRX	
+    rts
+.endproc	
diff --git a/libsrc/telestrat/gotoxy.s b/libsrc/telestrat/gotoxy.s
index 18e010ae2..fb659d968 100644
--- a/libsrc/telestrat/gotoxy.s
+++ b/libsrc/telestrat/gotoxy.s
@@ -8,6 +8,8 @@
 
 
 .proc _gotoxy
+   ; This function move only cursor for display, it does not move the prompt position
+   ; in telemon, there is position for prompt, and another for the cursor
    sta SCRY
    jsr popa
    sta SCRX
-- 
2.39.5