Added CAS support to the example game

1 files changed, 164 insertions, 0 deletions

diff --git a/tools/mkcas.py b/tools/mkcas.py
new file mode 100755
index 0000000..267270d
--- /dev/null
+++ b/tools/mkcas.py
@@ -0,0 +1,164 @@
+#!/usr/bin/env python3
+#
+# Copyright (C) 2020-2022 by Juan J. Martinez <jjm@usebox.net>
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+#
+__version__ = "1.1"
+
+import os
+from argparse import ArgumentParser
+
+DEF_ADDR = 0x4000
+TYPES = ("binary", "basic", "ascii", "custom-header", "custom")
+TYPE_BLOCK = {
+    "binary": bytes((0xD0 for _ in range(10))),
+    "basic": bytes((0xD3 for _ in range(10))),
+    "ascii": bytes((0xEA for _ in range(10))),
+}
+
+BLOCK_ID = bytes((0x1F, 0xA6, 0xDE, 0xBA, 0xCC, 0x13, 0x7D, 0x74))
+
+
+def write_word(fd, word):
+    fd.write(bytes((word & 0xFF, word >> 8)))
+
+
+def auto_int(value):
+    return int(value, 0)
+
+
+def main():
+
+    parser = ArgumentParser(
+        description="Make a CAS file for the MSX",
+        epilog="Copyright (C) 2020-2022 Juan J Martinez <jjm@usebox.net>",
+    )
+
+    parser.add_argument(
+        "--version", action="version", version="%(prog)s " + __version__
+    )
+    parser.add_argument(
+        "-a",
+        "--add",
+        dest="add",
+        action="store_true",
+        help="append to the existing CAS file instead of creating a new one",
+    )
+    parser.add_argument(
+        "--name",
+        dest="name",
+        default=None,
+        type=str,
+        help="name to use for the file (limit 6 chars, defaults to the file name)",
+    )
+    parser.add_argument(
+        "--addr",
+        dest="addr",
+        default=DEF_ADDR,
+        type=auto_int,
+        help="address to load if binary file (default: 0x%04x)" % DEF_ADDR,
+    )
+    parser.add_argument(
+        "--exec",
+        dest="exec",
+        default=DEF_ADDR,
+        type=auto_int,
+        help="address to exec if binary file (default: 0x%04x)" % DEF_ADDR,
+    )
+
+    parser.add_argument("output", help="target .CAS file")
+    parser.add_argument("type", help="file type", choices=TYPES)
+    parser.add_argument("file", help="input file")
+
+    args = parser.parse_args()
+
+    if args.add:
+        flags = "ab"
+    else:
+        flags = "wb"
+
+    with open(args.output, flags) as out:
+
+        if args.name:
+            name = args.name
+        else:
+            name = os.path.basename(args.file)
+
+        with open(args.file, "rb") as inf:
+            data = inf.read()
+
+        out.write(BLOCK_ID)
+
+        if args.type == "ascii":
+
+            out.write(TYPE_BLOCK[args.type])
+            out.write(name[:6].ljust(6).encode("ascii"))
+
+            for b in range(0, len(data), 256):
+                out.write(BLOCK_ID)
+                out.write(data[b : b + 256])
+
+            padding = 256 - (len(data) % 256)
+            if padding == 256:
+                out.write(BLOCK_ID)
+            out.write(bytes((0x1A for _ in range(padding))))
+
+        elif args.type == "basic":
+
+            out.write(TYPE_BLOCK[args.type])
+            out.write(name[:6].ljust(6).encode("ascii"))
+            out.write(BLOCK_ID)
+            out.write(data)
+
+        elif args.type == "binary":
+
+            addr = args.addr
+            exec_addr = args.exec
+            end_addr = addr + len(data) - 1
+
+            if end_addr > 0xFFFF:
+                parser.error("Binary doesn't fit in memory")
+
+            out.write(TYPE_BLOCK[args.type])
+            out.write(name[:6].ljust(6).encode("ascii"))
+
+            out.write(BLOCK_ID)
+            write_word(out, addr)
+            write_word(out, end_addr)
+            write_word(out, exec_addr)
+
+            out.write(data)
+
+        elif args.type == "custom-header":
+
+            addr = args.addr
+            length = len(data)
+
+            write_word(out, addr)
+            write_word(out, length)
+            out.write(data)
+
+        else:
+            # custom
+            out.write(data)
+
+
+if __name__ == "__main__":
+    main()