Image Map Image Map
Results 1 to 3 of 3

Thread: VTech 3.5" floppy drive compatiblity information

  1. #1
    Join Date
    Jan 2013
    Marietta, GA

    Default VTech 3.5" floppy drive compatiblity information

    A while back I acquired a VTech (Video Technology Computers Ltd) Laser 3.5" floppy disk drive. One would expect that a 3.5" floppy drive for an Apple II clone would work with other Apple II computers, but this is not the case.

    The Apple II world of 3.5" drives are a confusing mess of incompatible models and controllers (some combinations of which can go boom!). Various Internet resources were not crystal clear about what this drive is compatible with, so I am posting my findings here.

    There are two very good resources that discuss drive and controller compatibility, but they don't discuss clones or integrated controllers.

    The Vtech Laser 3.5" floppy drive is a clone of the Macintosh "Apple 800K External" M131, but has a manual eject button.

    The Laser 3.5" floppy drive is compatible with:
    II+/IIe/IIgs with Vtech UDC card
    Laser 128 (later models)/128ex

    The Laser 3.5" floppy drive is NOT compatible with:
    II+/IIe/IIgs with any other 3.5" cards
    IIc/IIc Plus
    Laser 128 early model (type with slits in the cover, reported may/may not work)

    Yes, that's right, this drive is really for the Macintosh, but works with and was sold for the Laser 128/128EX Apple II clone.

    The Laser 128 itself supports most Apple 3.5" drives. Its support is equivalent to the Vtech UDC card, a very powerful add-on for the Apple II+/IIe/IIgs.

    Reportedly, the Laser 128 SmartPort supports:
    Apple IIe/IIc UniDisks (3.5" and 5.25" models)
    Macintosh 3.5" drives (the ones without the buttons)
    Apple IIGS daisy-chainable 3.5" drives and Apple 5.25" disks
    Chinook CT-series 20 MB to 100 MB SmartPort hard drives

    (Although according to the resources above, mixing an Apple UniDisk 3.5" and VTech Universal Disk Controller card may go boom. Not the case for the Laser 128?)

    The Laser 128 SmartPort can support two 800K 3.5" drives, two 140K 5.25" drives, and one 100 MB CT100 hard drive simultaneously daisy-chained to each other.

  2. #2


    The Laser 3.5" drive lacks the logic found on the daisy chain board on the newer Apple 3.5" Drive that was included with the Apple IIgs, thus will be Macintosh compatible only.

  3. #3
    Join Date
    Jan 2013
    Marietta, GA


    Just a little more information, the specific model is LASER FD-356. FCC ID is BNX84H80-2204. The possibly meaningless number "802" is printed on a large sticker.

    Both the Laser 128 and UDC manual refer to this Laser floppy drive as the LASER FD-356 3.5" drive. There were apparently two versions, the FD-356 and FD-356DC. The latter would have daisy chain support. The regular one, like this one, has no daisy chain port on the back. Just a plastic break-out cover where the port would be.

    The above resources fail to mention that the Apple IIc with the fist (version 255) ROM revision supports NO 3.5" floppy drives at all. This can be rectified by performing a ROM upgrade. But as far as I can tell, this still only supports the one UniDisk 3.5" model (intelligent drive). IIc Plus ROMs can not be used as the IIc Plus has significantly different hardware.

    The Laser 128 manual says the Laser 128 computer officially supports:
    - LASER FD-100c 5.25" drives or compatibles
    - Unidisk 5.25 drives or compatibles
    - LASER FD-356 3.5" drives or compatibles
    - Unidisk 3.5 drives or compatibles

    The Laser 128 tech manual then goes on to describe the two types of 3.5" drives:
    The disk drives which are supported by the
    computer can be classified into two
    categories: intelligent and non-intelligent.
    Intelligent disk drives have dedicated
    microprocessor and hardware for controlling
    the disk read/write operation and it only
    receives high-level commands from the host
    computer. These include the Unidisk
    5.25/3.5 compatible disk drives.
    All the other disk drives supported by the
    computer are non-intelligent in the sense
    that all or most of the disk read/write
    operations have to be directly controlled by
    the CPU.

    Interfacing with non-intelligent 3.5" disk

    These refer to LASER FD-356 compatible
    3.5" disk drives They are double-side,
    double-density drives with a formatted
    storage capacity of 800 K-bytes.

    Interfacing with intelligent disk drives

    Intelligent disk drives include the Unidisk
    5.25 and Unidisk 3.5 compatible disk
    drives. They have built-in microprocessor,
    ROM, RAM and other circuitries for
    controlling the disk read/write operations
    and are effectively microcomputers on their
    own. They only receive and process highlevel
    commands (such as read status, format,
    read block and write block etc.) from the
    host computer.


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts