first commit

make_adf.py

@@ -0,0 +1,48 @@
+#!/usr/bin/env python3
+import struct
+
+def calc_bootblock_checksum(data):
+    """Calculate Amiga bootblock checksum"""
+    # Clear checksum field first
+    data = bytearray(data)
+    struct.pack_into('>I', data, 4, 0)
+    
+    # Sum all longwords with carry
+    chksum = 0
+    for i in range(0, 1024, 4):
+        val = struct.unpack_from('>I', data, i)[0]
+        chksum += val
+        if chksum > 0xFFFFFFFF:
+            chksum = (chksum & 0xFFFFFFFF) + 1
+    
+    # Return NOT of sum
+    chksum = (~chksum) & 0xFFFFFFFF
+    return chksum
+
+# Read files
+with open('boot.bin', 'rb') as f:
+    boot = bytearray(f.read())
+
+with open('game.bin', 'rb') as f:
+    game = f.read()
+
+# Pad bootblock to 1024 bytes
+if len(boot) < 1024:
+    boot += b'\x00' * (1024 - len(boot))
+
+# Calculate and set checksum
+chksum = calc_bootblock_checksum(boot)
+struct.pack_into('>I', boot, 4, chksum)
+print(f"Bootblock checksum: 0x{chksum:08X}")
+
+# Create ADF
+adf = bytearray(880 * 1024)
+adf[0:1024] = boot
+adf[1024:1024+len(game)] = game
+
+# Write ADF
+with open('giochino.adf', 'wb') as f:
+    f.write(adf)
+
+print(f"Created giochino.adf ({len(adf)} bytes)")
+print(f"Game size: {len(game)} bytes")