Last modified on 3 January 2010, at 14:53

Vortex Disc Drives

Revision as of 14:53, 3 January 2010 by Nocash (Talk | contribs) (M1)

Disc drives from Vortex.

F1

A 5.25" disc drive. 80 tracks and 704Kb.

  • F1 - S Single 5.25" drive with controller.
  • F1 - Z Single 5.25" drive without controller.
  • F1 - D Double 5.25" drive with controller.

The disc drive also was available as an extended versions :

  • F1 - XRS which also contains a RS232 interface.
  • F1 - X which can be updated with a RS232 interface.

On the F1-S/D Controllers the Disc operation system VDOS 1.0 on ROM was included.

On the F1-X/XRS Controllers the Disc operation system VDOS 2.0 on ROM was included.

M1

A 3.5" disc drive. 80 tracks and 704KB Formatted per Disk.

  • M1 - S Single 3.5" drive with controller.
  • M1 - Z Single 3.5" drive without controller.
  • M1 - D Double 3.5" drive with controller.

The disc drive also was available as an extended version:

  • M1-XRS which also contains a RS232 interface.
  • M1-X which can be updated with a RS232 interface.

On the M1-S/D Controllers the Disc operation system VDOS 1.0 on ROM was included.

On the M1-X/XRS Controllers the Disc operation system VDOS 2.0 on ROM was included.

Tape

The Vortex disc drive controller

The Vortex disc drive controler was similar to Amstrads own controller on DDI-1.

It used the same controler chip, the NEC765.

It has VDOS on ROM.

I/O Ports

 Standard Addresses (same as used by AMSDOS):
   FB7Eh 765 FDC (internal) Status Register (R)
   FB7Fh 765 FDC (internal) Data Register (R/W)
 Special Addresses (secondary FDC):
   FBF6h 765 FDC (Vortex,ext) Status Register (Read)
   FBF7h 765 FDC (Vortex,ext) Data Register (R/W)
 (The Special addresses are mentioned in the manual
 for the Vortex -X drives) (but apparently they are referring
 to other/older Vortex drives, not the -X drives)

The Special addresses are used only on CPC 664/6128 and only if the Vortex drive includes an FDC chip.

  • Note1: The -Z and -X drives do not include FDC chips.
  • Note2: The -S and -D drives do reportedly work only on CPC 464 (?).

So, not sure if/when the Special addresses are used at all?

 RS232 Ports (for -X drives with RS232)
   FADC/FADD=Serial Data/Control
   FBDC/FBDD/FBDF=Counter 0/1/Mode.
 So it's probably compatible with Amstrad/Pace 
 (and probably also including, but not using,
 Channel B Ports FADE/FADF and FBDE).

Vortex Disk Format

Sector numbers are 01h..09h (same as AMSDOS IBM Format, but with a 9th sector) Disks are Double-Sided, Double Density, 80 Tracks, 9 Sectors Total capacity is 720K (704K available):

  • First 9K contain two System Tracks (eg. CP/M Bootstrap)
  • Next 4K contain directory (see Note)
  • Next 704K are data (allocated in 4K blocks) (aka 4K clusters)
  • Last 3K are unused (due to 4K allocation size)

Note: According to the manual, the directory can hold 128 entries under VDOS2.0 (whole 4K used), but only 64 entries under VDOS1.0 (only half of the 4K area used).

The Vortex -Z drives do not seem to include any VDOS ROM (so they do support only normal 40-Track AMSDOS Formats, but NOT the 80-Track Vortex format).

Pictures

Manuals