Virtual Tape Utilities

Reading and Writing tapes does not require a special utility in and of itself. Audacity, Goldwave, or any other audio recording software will work, because tapes are, in fact, just audio. There is a page devoted to how to read TRS-80 tapes into WAV format here.

What is the issue, is what to do with a WAV file once you have it. That is what this page is for. It has utilities that will convert WAVs to CAS format for use in an emulator, and back again. It has utilities that will convert high speed (1500 baud) tapes to Level II (500 baud) or even Level 1 (250 baud) and back again.

This utility is in the form of an extremely powerful web page.

The web page can be found at https://www.my-trs-80.com/cassette/. You can drag and drop a WAV, CAS, or BAS file and from there see the individual pulses of the WAV (original and filtered). You can click on the BASIC or Machine Language output listing and see the individual clock pulses in the WAV which gave rise to whatever you are pointing to. You can run the program in a virtual emulator in the browser. And, of course, you can export the corrected WAV to WAV, BAS, Binary, or CAS.

Source can be downloaded from GITHUB.

The standalone version of this tool has expanded way beyond this function, so it is discussed on the Multi-Utilities Page.

From a cassette features standpoint, the command line tool does the following:

Cassette Inspection and Extraction

• File identification: Identifies CAS images, WAV recordings, and cassette program formats, reporting embedded filenames and encoding information when available.
• WAV information: Displays additional recording metadata with info --verbose.
• Automated cataloging: Exports file information in JSON format with info --json.
• Cassette directory listings: Lists programs and their baud rates within CAS images and WAV recordings, including multi-program cassettes.
• Program extraction: Extracts individual programs from CAS images or WAV recordings into an existing directory. Supports lowercase output filenames and adds suffixes to avoid collisions between filenames differing only in case.

Cassette Conversion and Creation

• WAV decoding: Reads cassette recordings at any sampling rate, with 8-bit or 16-bit samples and mono or stereo audio.
• WAV-to-CAS conversion: Converts recorded cassette audio into compact CAS images that retain cassette synchronization information and high-speed start bits.
• WAV generation: Creates cassette audio from BASIC programs, cassette machine-code files, CAS images, and supported disk-format programs.
• Multi-program cassette creation: Combines multiple programs or existing cassette contents into a single CAS image or WAV recording.
• Disk-to-cassette conversion: Extracts files from supported floppy images for cassette output, including WAV generation. Converting a file does not guarantee that a program requiring disk services will run from cassette.
• Baud-rate selection: Preserves the input cassette speed when known, defaults to 500 baud when it cannot determine a speed, and allows an explicit override with --baud, including 1500-baud output.
• High-speed CAS compatibility: Reads high-speed CAS images whose stored data is not byte-aligned.

Program Formats and Editing

• Machine-code conversion: Converts disk-format .CMD programs to cassette-format .3BN files.
• BASIC conversion: Reads tokenized and plain-text BASIC, exports readable .ASC listings, writes tokenized .BAS files, and converts supported BASIC programs for cassette output.
• Level I support: Reads 250-baud .L1 cassette files containing BASIC or system programs from Level I Model I or Model III machines.
• Execution-address repair: Reports a guessed start address for system programs lacking one and allows an explicit address with --start ADDRESS or automatic selection with --start auto.
• Raw-binary conversion: Converts .ROM and .BIN files to cassette machine-code format, using --start to specify both the load and execution addresses.
• EDTASM text export: Converts supported EDTASM files to readable .ASC text.

Assembly, Disassembly, and Testing

• Assembly to cassette formats: Assembles Z80 source directly into .3BN, .CAS, or .WAV files, with optional assembly listings and selectable cassette baud rates.
• Cassette disassembly: Disassembles machine-code programs directly from CAS images, WAV recordings, or standalone .3BN files. For multi-program cassettes, only the first program is disassembled.
• Disassembly control: Produces assembly source or formatted listings and accepts additional code entry points through --entry to help analyze relocated or otherwise unrecognized code.
• Emulator cassette mounting: Mounts a cassette with run --mount in.cas for use in the terminal-based TRS-80 emulator. One cassette can be mounted at a time, alongside floppy images.