From e001280dc275364912deab23f55a18334c713893 Mon Sep 17 00:00:00 2001
From: Sijmen Schoon <me@sijmenschoon.nl>
Date: Wed, 9 Dec 2020 09:01:02 +0100
Subject: [PATCH] Shuffle memory locations around a bit

---
 c64/day01.asm  |  3 +--
 c64/main.asm   | 41 ++++++++++++++++++-----------------------
 c64/math.asm   |  2 +-
 c64/screen.asm | 30 ++++++++++++++----------------
 4 files changed, 34 insertions(+), 42 deletions(-)

diff --git a/c64/day01.asm b/c64/day01.asm
index d58ad25..ef84589 100644
--- a/c64/day01.asm
+++ b/c64/day01.asm
@@ -18,7 +18,7 @@
 .const remainder      = $24
 
 // Need to be $03 and $fd due to multiply_16bit_unsigned
-.const outer_value    = $03
+.const outer_value    = $26
 .const inner_value    = $fd
 
 day01:
@@ -112,7 +112,6 @@ day01:
     iny
     lda (outer_pointer), y
     bne !not_zero+
-    .break
     jmp !error+
 !not_zero:
 
diff --git a/c64/main.asm b/c64/main.asm
index cccb712..ab54097 100644
--- a/c64/main.asm
+++ b/c64/main.asm
@@ -4,29 +4,7 @@
 
     BasicUpstart2(main)
 
-* = $8000
-    .align $100
-* = * "Square table"
-square1_lo:
-    .fill 512, 0
-square1_hi:
-    .fill 512, 0
-square2_lo:
-    .fill 512, 0
-square2_hi:
-    .fill 512, 0
-
-* = * "Day 01 Input"
-day01_input:
-    .import text "../rust/inputs/day01"
-    .byte 0
-* = * "Day 01 Input End"
-
-//* = $8000 "Cartridge ROM"
-
-//* = $a000 "Basic ROM"
-
-* = $c000 "Main program"
+* = $0900 "Main program"
 .const SCREEN_RAM = $0400
 .const COLOR_RAM = $d800
 
@@ -72,3 +50,20 @@ buffer:
 #import "day01.asm"
 #import "screen.asm"
 #import "math.asm"
+
+* = *     "Day 01 Input"
+day01_input:
+    .import text "../rust/inputs/day01"
+    .byte 0
+
+    .align $100
+* = * "Square table"
+square1_lo:
+    .fill 512, 0
+square1_hi:
+    .fill 512, 0
+square2_lo:
+    .fill 512, 0
+square2_hi:
+    .fill 512, 0
+
diff --git a/c64/math.asm b/c64/math.asm
index 49d69a0..cae2234 100644
--- a/c64/math.asm
+++ b/c64/math.asm
@@ -4,7 +4,7 @@
 
 // Multiplication routines found on
 // https://codebase64.org/doku.php?id=base:seriously_fast_multiplication
-.const T1=$03
+.const T1=$26
 .const T2=$fd
 .const PRODUCT=$22
 
diff --git a/c64/screen.asm b/c64/screen.asm
index 2370ddd..a6f7b01 100644
--- a/c64/screen.asm
+++ b/c64/screen.asm
@@ -107,39 +107,37 @@ write_string:
     ldx #0
     ldy #0
 
-!loop:
-    lda ($03), y
-    beq !done+
+    !loop:
+        lda ($03), y
+        beq !done+
 
-    cmp #'\r'
-    beq !carriage_return+
-    cmp #'\n'
-    beq !newline+
+        iny
 
-    sta (cursor_pointer_lo, x)
+        cmp #'\r'
+        beq !carriage_return+
+        cmp #'\n'
+        beq !newline+
 
-    i16_inc(cursor_pointer_lo)
-
-    iny
+        sta (cursor_pointer_lo, x)
+        i16_inc(cursor_pointer_lo)
     jmp !loop-
 
 !newline:
     jsr print_newline
+    jmp !loop-
 
 !carriage_return:
     jsr print_carriage_return
-
-    iny
     jmp !loop-
 
 !done:
     rts
 
 
-.macro i16_print_hex_0x(lo, hi) {
-    lda hi
+.macro i16_print_hex_0x(addr) {
+    lda addr + 1
     jsr print_hex_0x
-    lda lo
+    lda addr
     jsr print_hex
 }