In this Commodore 64 coding video, I look at how to transfer a multiload turbo tape game to disk. This involves understanding the tape loader, discovering the tape data format, extracting the files, altering the code to load from disk, and creating a disk.

Debugging notes: [ Ссылка ]

00:00 Introduction, the objectives
00;35 Quick look at the game, Gauntlet
03:16 C64 Tape device schematic and CIA
05:52 Analyse tape loader behaviour
09:58 Main loader code entry point
11:29 Claimed the kernal load routine vector
14:08 Using a CIA timer and IRQ on the tape pulse
15:34 Detect load complete and verify checksum
16:10 Tape read pulse interrupt, measuring time
18:03 Decoding 0 or 1 bits from the tape
19:12 Converting a bit stream to data bytes
21:06 Byte read state machine entry
21:28 Understand the tape data structure
31:45 Finding the tape pulse timings
33:09 Using TapeTool to extract data from the tape
36:42 Checking extracted file data
37:40 Change the game code to read from disk
45:31 Creating a disk image
50:07 Testing the disk
52:41 Displays the title screen
55:39 How the game chooses the level data file
58:04 First level works
58:48 Level 8 load... Works!
59:39 Minimising code changes

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