From 9e6a96f93a59af8ae45eaefbade11c61e6654f59 Mon Sep 17 00:00:00 2001
From: Kilian Hofmann <llego03@yahoo.com>
Date: Sun, 27 Sep 2026 01:21:42 +0200
Subject: [PATCH] Fix BASIC

---
 msbasic/defines_kilian.s | 25 ++++++++++++------------
 msbasic/init.s           |  8 ++++++++
 src/io.c                 | 15 +++++++++++++++
 src/memoryMap.c          | 41 ++++++++++++++++++++++++----------------
 4 files changed, 60 insertions(+), 29 deletions(-)

diff --git a/msbasic/defines_kilian.s b/msbasic/defines_kilian.s
index c55b11a..391d925 100644
--- a/msbasic/defines_kilian.s
+++ b/msbasic/defines_kilian.s
@@ -1,21 +1,20 @@
 ; configuration
-CONFIG_2A := 1
+CONFIG_2A           := 1
 CONFIG_SCRTCH_ORDER := 2
 
 ; zero page
-ZP_START0 = $00
-ZP_START1 = $02
-ZP_START2 = $0C
-ZP_START3 = $62
-ZP_START4 = $6D
+ZP_START0           = $00
+ZP_START1           = $02
+ZP_START2           = $0C
+ZP_START3           = $62
+ZP_START4           = $6D
 
 ; extra/override ZP variables
-USR				:= GORESTART ; XXX
+USR                 := GORESTART ; XXX
 
 ; constants
-SPACE_FOR_GOSUB := $3E
-STACK_TOP		:= $FA
-WIDTH			:= 40
-WIDTH2			:= 30
-
-RAMSTART2		:= $0400
+SPACE_FOR_GOSUB     := $3E
+STACK_TOP           := $FA
+WIDTH               := 40
+WIDTH2              := 30
+RAMSTART2           := $0400
diff --git a/msbasic/init.s b/msbasic/init.s
index 077d981..f1de786 100644
--- a/msbasic/init.s
+++ b/msbasic/init.s
@@ -204,9 +204,17 @@ L4098:
         ldx     #TEMPST
         stx     TEMPPT
 .ifndef CONFIG_CBM_ALL
+  .ifdef KILIAN
+        lda #<$BC00
+        sta MEMSIZ
+        lda #>$BC00
+        sta MEMSIZ+1
+        jmp L4106
+  .else
         lda     #<QT_MEMORY_SIZE
         ldy     #>QT_MEMORY_SIZE
         jsr     STROUT
+  .endif
   .ifdef APPLE
         jsr     INLINX
   .else
diff --git a/src/io.c b/src/io.c
index 1cf8616..e73abbe 100644
--- a/src/io.c
+++ b/src/io.c
@@ -13,5 +13,20 @@ int getChar(void) {
 
   int c = getchar();
 
+  // Specifically send FF for EOF to trigger echo cancellation
+  if (c == EOF) {
+    return 0xFF;
+  }
+
+  // BASIC expects CR always
+  if (c == '\n') {
+    return '\r';
+  }
+
+  // BASIC is uppercase only
+  if (c >= 'a' && c <= 'z') {
+    c = c - 'a' + 'A';
+  }
+
   return c;
 }
\ No newline at end of file
diff --git a/src/memoryMap.c b/src/memoryMap.c
index 3f7de6c..a056d42 100644
--- a/src/memoryMap.c
+++ b/src/memoryMap.c
@@ -26,25 +26,34 @@ uint8_t readMemory(uint16_t address, uint8_t *ram, uint8_t *rom) {
 }
 
 void writeMemory(uint16_t address, uint8_t value, uint8_t *ram) {
-  if ((address < RAM_SIZE && address < IO_BASE) || address >= ROM_BASE) {
-    if (address < ROM_BASE && ram[IO_BASE + ROM_BANKED_OUT] != 0) {
+  /* Normal RAM */
+  if (address < IO_BASE) {
+    ram[address] = value;
+    return;
+  }
+
+  /* ROM area */
+  if (address >= ROM_BASE) {
+    if (ram[IO_BASE + ROM_BANKED_OUT] != 0) {
       ram[address] = value;
     }
-  } else {
-    uint16_t _address = address - IO_BASE;
-    switch (_address) {
-      case SCREEN_ADDRESS: {
-        putChar(value);
-        break;
-      }
-      case ROM_BANKED_OUT: {
-        ram[IO_BASE + ROM_BANKED_OUT] = value;
-        break;
-      }
+    return;
+  }
 
-      default:
-        break;
-    }
+  /* I/O area */
+  uint16_t _address = address - IO_BASE;
+
+  switch (_address) {
+    case SCREEN_ADDRESS:
+      putChar(value);
+      break;
+
+    case ROM_BANKED_OUT:
+      ram[IO_BASE + ROM_BANKED_OUT] = value;
+      break;
+
+    default:
+      break;
   }
 }