page_title: Commodore Datasette
section_title: Description and history
hierarchical_section_title: Commodore Datasette / Description and history
caption_attribution_description: This is a real &quot;screenshot&quot; from a Commodore PET 2001. It doesn't have to boot and -- as you see -- the BASIC interpreter only takes about 800bytes in RAM&#160;;-) The &quot;L&quot; key doesn't work good, so it took two runs to make it searching a program from the data tape. Unfortunately it still doesn't fully work again, so it won't load the world's first Space Invader implementation&#160;:-/
context_page_description: The Commodore 1530 Datasette, later also Datassette, is Commodore's dedicated magnetic tape data storage device. Using compact cassettes as the storage medium, it provides inexpensive storage to Commodore's 8-bit home/personal computers, notably the PET, VIC-20, and C64. A physically similar model, Commodore 1531, was made for the Commodore 16 and Plus/4 series computers.
context_section_description: Typical compact cassette interfaces of the late 1970s use a small controller in the computer to convert digital data to and from analog tones. The interface is then connected to the cassette deck using normal sound wiring like RCA jacks or 3.5mm phone jacks. This sort of system was used on the Apple II and Color Computer, as well as many S-100 bus systems, and allow them to be used with any cassette player with suitable connections.
  In the Datasette, instead of writing two tones to tape to indicate bits, patterns of square waves are used, including a parity bit. Programs are written twice to tape for error correction; if an error is detected when reading the first recording, the computer corrects it with data from the second. The Datasette has built-in analog-to-digital converters and audio filters to convert the computer's digital data into analog sound and vice versa. Connection to the computer is done via a proprietary edge connector (Commodore 1530) or mini-DIN connector (1531). The absence of recordable audio signals on this interface makes the Datasette and clones the only cassette recorders usable with Commodore computers, until aftermarket converters made the use of ordinary recorders possible.
  Because of its digital format the Datasette is both more reliable than other data cassette systems and very slow, transferring data at around 50 bytes per second; even the very slow Commodore 1541 floppy drive is much faster. After the Datasette's launch, however, special turbo tape software appeared, providing much faster tape operation (loading and saving). Such software was integrated into most commercial prerecorded applications (mostly games), as well as being available separately for loading and saving the users' homemade programs and data. These programs were only widely used in Europe, as the US market had long since moved onto disks.
  Datasettes can typically store about 100 kByte per 30 minute side. The use of turbo tape and other fast loaders increased this number to roughly 1000 kByte.
  The Datasette was more popular outside than inside the United States. U.S. Gold, which imported American computer games to Britain, often had to wait until they were converted from disk because most British Commodore 64 owners used tape, while the US magazine Compute!'s Gazette reported that by 1983 "90 percent of new Commodore 64 owners bought a disk drive with their computer". Computer Gaming World reported in 1986 that British cassette-based software had failed in the United States because "97% of the Commodore systems in the USA have disk drives"; by contrast, MicroProse reported in 1987 that 80% of its 100,000 sales of Gunship in the UK were on cassette. In the United States disk drives quickly became standard, despite the 1541 costing roughly five times as much as a Datasette. In most parts of Europe, the Datasette was the medium of choice for several years after its launch, although floppy disk drives were generally available. The inexpensive and widely available audio cassettes made the Datasette a good choice for the budget-aware home computer mass market.
caption: The Datasette loading process
exif: {"Image ImageDescription": "Digital StillCamera", "Image Make": "CAMERA", "Image Model": "5MP-9A3", "Image Orientation": "Horizontal (normal)", "Image XResolution": "72", "Image YResolution": "72", "Image ResolutionUnit": "Pixels/Inch", "Image Software": "GIMP 2.4.2", "Image DateTime": "2008:08:04 01:36:26", "Image YCbCrPositioning": "Co-sited", "Image ExifOffset": "232", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail Orientation": "Horizontal (normal)", "Thumbnail XResolution": "72", "Thumbnail YResolution": "72", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "964", "Thumbnail JPEGInterchangeFormatLength": "5495", "Thumbnail YCbCrPositioning": "Co-sited", "EXIF ExposureTime": "1/20", "EXIF FNumber": "14/5", "EXIF ExposureProgram": "Program Normal", "EXIF ISOSpeedRatings": "200", "EXIF ExifVersion": "0220", "EXIF DateTimeOriginal": "2008:08:19 16:53:50", "EXIF DateTimeDigitized": "2008:08:19 16:53:50", "EXIF ComponentsConfiguration": "YCbCr", "EXIF ShutterSpeedValue": "43/10", "EXIF ApertureValue": "3", "EXIF ExposureBiasValue": "0", "EXIF MaxApertureValue": "31/10", "EXIF MeteringMode": "CenterWeightedAverage", "EXIF LightSource": "Unknown", "EXIF Flash": "Flash did not fire", "EXIF FlashPixVersion": "0100", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "1280", "EXIF ExifImageLength": "960", "EXIF RelatedSoundFile": "", "Interoperability InteroperabilityIndex": "R98", "Interoperability InteroperabilityVersion": "[48, 49, 48, 48]", "EXIF InteroperabilityOffset": "816", "EXIF FileSource": "Digital Camera", "EXIF CustomRendered": "Normal", "EXIF ExposureMode": "Auto Exposure", "EXIF WhiteBalance": "Auto", "EXIF DigitalZoomRatio": "0", "EXIF FocalLengthIn35mmFilm": "35", "EXIF SceneCaptureType": "Standard", "EXIF GainControl": "None", "EXIF Contrast": "Normal", "EXIF Saturation": "Normal", "EXIF Sharpness": "Normal", "EXIF SubjectDistanceRange": "1"}