From 6671a92a8edbdadfa904923c98c665431ea199db Mon Sep 17 00:00:00 2001
From: Karri Kaksonen <karri@sipo.fi>
Date: Mon, 18 Apr 2022 13:49:29 +0300
Subject: [PATCH] Not sharing umula0 and fix cursor bug

---
 libsrc/atari7800/cputc.s          |  3 +--
 libsrc/atari7800/mono_cputc.s     |  8 ++++----
 libsrc/atari7800/mono_setcursor.s | 11 +++++------
 libsrc/atari7800/setcursor.s      | 28 +++++++++++++++++++++++++++-
 4 files changed, 37 insertions(+), 13 deletions(-)

diff --git a/libsrc/atari7800/cputc.s b/libsrc/atari7800/cputc.s
index fb95277d2..9ec84bfe5 100644
--- a/libsrc/atari7800/cputc.s
+++ b/libsrc/atari7800/cputc.s
@@ -6,8 +6,7 @@
 ;
 
         .export         _cputc
-        .export         umula0
-        .import         _gotoxy, gotox, gotoy, pusha0
+        .import         gotox, gotoy, pusha0
         .import         pushax
         .import         _screen
         .import         txtcolor
diff --git a/libsrc/atari7800/mono_cputc.s b/libsrc/atari7800/mono_cputc.s
index 4a7e5638c..aa6787e05 100644
--- a/libsrc/atari7800/mono_cputc.s
+++ b/libsrc/atari7800/mono_cputc.s
@@ -6,7 +6,7 @@
 ;
 
         .export         _mono_cputc
-        .import         _mono_gotoxy, _mono_gotox, _mono_gotoy, pusha0
+        .import         mono_gotox, mono_gotoy, pusha0
         .import         pushax
         .import         _mono_screen
 
@@ -52,7 +52,7 @@ umula0:
         cmp     #$0A            ; LF
         bne     @L4
 @L1:    lda     #0              ; newline
-        jsr     _mono_gotox
+        jsr     mono_gotox
         lda     CURS_Y
         cmp     #(screenrows-1)
         bne     @L2
@@ -60,7 +60,7 @@ umula0:
         beq     @L3
 @L2:    clc
         adc     #1
-@L3:    jmp     _mono_gotoy
+@L3:    jmp     mono_gotoy
 
 @L4:
         pha
@@ -96,7 +96,7 @@ umula0:
         beq     @L1
         clc
         adc     #1
-        jmp     _mono_gotox
+        jmp     mono_gotox
 
         .endproc
 
diff --git a/libsrc/atari7800/mono_setcursor.s b/libsrc/atari7800/mono_setcursor.s
index 060f45cde..fa02b1744 100644
--- a/libsrc/atari7800/mono_setcursor.s
+++ b/libsrc/atari7800/mono_setcursor.s
@@ -23,7 +23,7 @@
 ; definitely not allow direct access to the variables.
 ;
 
-        .export         mono_gotoxy, _mono_gotoxy, _mono_gotox, _mono_gotoy
+        .export         mono_gotoxy, _mono_gotoxy, mono_gotox, mono_gotoy
         .constructor    mono_init_cursor
         .interruptor    mono_blink_cursor
 
@@ -96,7 +96,6 @@ umula0:
         adc     #<_mono_zones
         sta     cursorzone      ; calculate new cursorzone
         txa
-        clc
         adc     #>_mono_zones
         sta     cursorzone+1
         rts
@@ -118,7 +117,7 @@ umula0:
 ; Enable cursor
 ; if showcursor cursorzone[1] = 31
 ;
-        .proc   _mono_gotoy
+        .proc   mono_gotoy
 
         pha
         lda     CURS_Y
@@ -143,7 +142,7 @@ umula0:
 ; You also need to set the hpos offset to the correct value on this line
 ; cursorzone[3] = 4 * CURS_X?
 ;
-        .proc   _mono_gotox
+        .proc   mono_gotox
 
         sta     CURS_X
         ldy     #3
@@ -160,9 +159,9 @@ umula0:
 ;
         .proc   _mono_gotoxy
 
-        jsr     _mono_gotoy
+        jsr     mono_gotoy
         jsr     popa
-        jsr     _mono_gotox
+        jsr     mono_gotox
         rts
         .endproc
 
diff --git a/libsrc/atari7800/setcursor.s b/libsrc/atari7800/setcursor.s
index 99e051cff..d94eb8094 100644
--- a/libsrc/atari7800/setcursor.s
+++ b/libsrc/atari7800/setcursor.s
@@ -31,7 +31,6 @@
         .import         _zones
         .import         cursor
         .import         pusha, incsp1, pusha0, pushax, popa
-        .import         umula0
         .include        "atari7800.inc"
         .include        "extzp.inc"
 
@@ -47,6 +46,33 @@ blink_time:
 
         .code
 
+;---------------------------------------------------------------------------
+; 8x16 routine
+
+umula0:
+        ldy     #8                 ; Number of bits
+        lda     #0
+        lsr     ptr7800            ; Get first bit into carry
+@L0:    bcc     @L1
+
+        clc
+        adc     ptrtmp
+        tax
+        lda     ptrtmp+1           ; hi byte of left op
+        clc
+        adc     ptr7800+1
+        sta     ptr7800+1
+        txa
+
+@L1:    ror     ptr7800+1
+        ror     a
+        ror     ptr7800
+        dey
+        bne     @L0
+        tax
+        lda     ptr7800            ; Load the result
+        rts
+
 ;-----------------------------------------------------------------------------
 ; Calculate cursorzone address
 ; You also need to set the cursorzone to point to the correct cursor Header