The later Professional-DOS Release variant from VTS Data
Since October 1987 in germany Professional-DOS was mainly sold by
VTS Data, instead of Mikrotronic. Because the floppy expansion
board got some minor changes (e.g. additional Jumpers), this
sections refers to the »VTS Release« variant.
Currently detailed informations about the VTS variant are not
known and so it is assumed, that there are no big differencies
to the hardware shown in the Release
The table below contains two pictures of the original packaging of
such a Professional-DOS Release sold by VTS Data. Additionally the
contributor sent the contents of the tool disk of his speeder. This
disk does not only contain the copy programs as the other
Professional-DOS tool disks, but an interactive demonstration for
the C64 and C128 (PAL and NTSC versions), which shows how to insert
the speeder into the different floppy drives and the main computer
(the language of this demo is german). It also refers to a Jumper
JP3, that has to be closed, when inserting Professional-DOS into a
C1541C disk drive.
The tool disk is missing the drive kernal ROM as with the tool
disks of other Professional-DOS versions. It does only contain
the kernal ROM for a C64 computer.
A Complete Professional-DOS Release set
Recently (December 2002) there was an auction on german
were most probably another VTS Data Version was sold. The
pictures show a whole box full with different EPROMs, the
drive board, an expansion port interface cartridge, a big
ROM switch and cables. It also contains the manual, the tool
disk and an assembly manual. The description from the
selling user also stated, that this system can be used
either with a C64, C128 or C128D and the floppy disk drives
1541, 1541C or 1571 and also the 1571 built into a C128D.
All the different EPROMs shown are an indication for the
truthfulness of this message.