Coleco ADAM Digital Data Pack

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Contrary to popular opinion, it did not require an expensive cassette to duplicate an ADAM Data Pack. Many different types of tapes have been used in copies, and even unbranded cheap bulk tape cassettes would work as long as the tape duplicator was of adequate quality. This fact is in contrast to the commonly assumed (but incorrect) idea that it takes a very high-quality cassette to work reliably under the conditions of the Adam drive. Even though the ADAM stores data at a high density and advances and rewinds the tape at high speeds (to do random access of data blocks), even bulk-bought inexpensive cassette tapes could be modded for use.  
 
Contrary to popular opinion, it did not require an expensive cassette to duplicate an ADAM Data Pack. Many different types of tapes have been used in copies, and even unbranded cheap bulk tape cassettes would work as long as the tape duplicator was of adequate quality. This fact is in contrast to the commonly assumed (but incorrect) idea that it takes a very high-quality cassette to work reliably under the conditions of the Adam drive. Even though the ADAM stores data at a high density and advances and rewinds the tape at high speeds (to do random access of data blocks), even bulk-bought inexpensive cassette tapes could be modded for use.  
  
ADAM only recognizes cassettes when they're formatted. So just drilling some holes will not make an ADAM recognize a homemade Data Pack. New, store-bought Adam tapes came pre-formatted way, but any other cassette being prepared for use on an Adam needs to be formatted first on a special machine designed for it, since the Adam itself wasn't able to format a tape. However, an easy solution is to simply copy an empty Digital Data Pack onto a blank audio cassette with properly drilled holes. Using just a commonly available tape copier and a drill, you could easily make your own blank formatted Digital Data Packs.
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ADAM only recognizes cassettes when they're formatted. So just drilling some holes in a blank audio tape will not make an ADAM recognize a homemade Data Pack. New, store-bought Adam tapes came pre-formatted way, but any other cassette being prepared for use on an Adam needs to be formatted first on a special machine designed for it, since the Adam itself wasn't able to format a tape. However, an easy solution is to simply copy an empty Digital Data Pack onto a blank audio cassette with properly drilled holes. Using just a commonly available tape copier and a drill, you could easily make your own blank formatted Digital Data Packs.
  
 
Both home-made or store-bought ADAM Digital Data Packs did suffer from occasional explosions due to the extreme high-speed of the drive. Sometimes the drive door for the Digital Data Pack could come loose, and the tape would explode inside the cassette shell, winding tape around the drive spindles.   
 
Both home-made or store-bought ADAM Digital Data Packs did suffer from occasional explosions due to the extreme high-speed of the drive. Sometimes the drive door for the Digital Data Pack could come loose, and the tape would explode inside the cassette shell, winding tape around the drive spindles.   

Revision as of 12:17, 8 September 2019

File Format
Name Coleco ADAM Digital Data Pack
Ontology
Released 1983

The Coleco Adam Digital Data Pack is a variant of an Audio Cassette used for data storage on a Coleco Adam home computer, storing data and programs (including Coleco Adam SmartBASIC tokenized files).

While these look like normal cassettes, they are not directly interchangeable; a hole on the case is in a different position than on a standard audio cassette, which prevents audio cassettes from being inserted into Coleco Adam tape drives or Adam data packs being inserted in audio cassette players, though "hardware hackers" have succeeded in making such uses by drilling appropriate holes.

Common tape copiers of the 1980s, such as ghetto-blasters and boom boxes were perfect for copying ADAM cassettes. After drilling the appropriate holes (a drill press made this easy), all it took was pressing PLAY on one cassette and RECORD on the other. An hour or so later, and you'd have a perfect Data Pack copy.

Contrary to popular opinion, it did not require an expensive cassette to duplicate an ADAM Data Pack. Many different types of tapes have been used in copies, and even unbranded cheap bulk tape cassettes would work as long as the tape duplicator was of adequate quality. This fact is in contrast to the commonly assumed (but incorrect) idea that it takes a very high-quality cassette to work reliably under the conditions of the Adam drive. Even though the ADAM stores data at a high density and advances and rewinds the tape at high speeds (to do random access of data blocks), even bulk-bought inexpensive cassette tapes could be modded for use.

ADAM only recognizes cassettes when they're formatted. So just drilling some holes in a blank audio tape will not make an ADAM recognize a homemade Data Pack. New, store-bought Adam tapes came pre-formatted way, but any other cassette being prepared for use on an Adam needs to be formatted first on a special machine designed for it, since the Adam itself wasn't able to format a tape. However, an easy solution is to simply copy an empty Digital Data Pack onto a blank audio cassette with properly drilled holes. Using just a commonly available tape copier and a drill, you could easily make your own blank formatted Digital Data Packs.

Both home-made or store-bought ADAM Digital Data Packs did suffer from occasional explosions due to the extreme high-speed of the drive. Sometimes the drive door for the Digital Data Pack could come loose, and the tape would explode inside the cassette shell, winding tape around the drive spindles.

The tape drive uses two tracks of the tape, and has two basic formats for storing data: GW and HE. Each of them stores a total of 256 kilobytes in 1-kilobyte blocks, using 128 blocks per track.

The GW format stores blocks 0 through 7F (hex) in order on the first track (track 0), and similarly 80 through FF on the second track (track 1).

The HE format stores 40 through 7F, then blocks 0 through 3F, on track 0, and 80 through FF in order on track 1.

GW-format tapes are used to store data sequentially without any directory structure or filesystem, and the Adam's operating system offers no ability to copy this format.

HE-format tapes can have an EOS file system (the native OS of the Adam) with a directory, and are treated similarly to disks by the Adam.

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