The best disk drive MB-02 is designated for computers compatible with ZX Spectrum 16k, 48k (gumak), +, Delta, Didaktik Gama, 128k, +2, +2A, +3.

Basic contens

Real time clock and whole exdended ram is powered by battery. Floppy disk controller in MB-02 allows control any four disk drives with size 5.25 or 3.5 and double or high density (DD or HD). Data transfrer speed: DD: 25 kB/s, HD: 50 kB/s.

Disk format

                 5.25/DS DD  3.5/5.25/DS DD  3.5/DS HD
                 ----------  --------------  ---------
Number of tracks ... 40 ......... 80 .......... 80
Sector per track .... 5 .......... 5 .......... 11
Sector lenght .... 1024 ....... 1024 ........ 1024 bytes
Capacity of disk .. 400 ........ 800 ........ 1760 kB
Formatted cap. .... 395 ........ 793 ........ 1759 kB
FAT length .......... 1 .......... 2 ........... 4 sectors

Disk must be error-free at least two sectors on track 0. This allows using disks what cannot be used on PC (PC needs whole track 0 error-free).

Integrity of important data structures (boot,FAT,direstories) is protect by manifold control checksums.

There you can more directories stored into not only tree structure on disk. All directories (root directory too) are fully dynamic - number if files in one directory is limited by total capacity of disk only. Each directory has not only a name but a identification number too. You can select this directory by this identification number. It's more simple - you must not remember path into this directory (in tree structure). It's more speed too.

The same as directories, each file has identification number too. It's his order in directory. You can access a file by this order number. It allows more quickly access file or for example more files with the same name in one directory.

Characters in file names is totally unlimited - name can contain any 10 characters as you want - the same as classic tape names.

Cache system

MB-02 has CACHE memory for increase speed disk operations. There are stored important information about disk [FAT,directory,...]. Disk drive head must not seek at track 0 before loading each block - it increases speed of loading 2 or 3 times. Size of cache is 7 kB in actual dos version (308) and will be extendable up to 210 kB in new dos version 400.


MB-02 does not want to be new standart compatible with itself only as more other disk systems.
MB-02 is compatible with tape - the most uses or widen medium.
MB-02 is compatible with tape - it means there are no need to modify programs what use tape for its work. [Tape emulation is realized like in ZX Spectrum emulators.]

Something for programmers

Compatibility with tape is realized by emulation ROM load-save routines on addresses #4c6 and #562. It allows any program what use will be work with diskette too. Program must call load-save into ROM #4c2-#4c6 and #556-#562. (cannot use own loaders).
Operating system allows disk control by three ways: (a) tape emulation by ROM load-save routines, (b) full support by basic commands, (c) many many system calls. Programmer can use these system calls in his own machine-code programs - it allows very simple disk control from these programs. Description of system calls is part of user documentation of disk system MB-02.
While data is loading or saving, processor Z80 must not do any time-critical operations. It means you can play music from interrupt. There are no need disable interrupt if data is loading/saving. It's important for demo-makers - there are possible make efect for example like music and wawed scroll "Loading next part".


MB-02 is making in czech factory 8BitCompany. Any information about MB-02 bussiness you can receive on address:

        Lucni 4570
        760 05 Zlin
        Czech republic
You can use telephone contact. Number of 8BitCompany is +420-67-43424.
And some prices. Sorry for Sk only, but I don't know prices in any other currency. But you can ask directly 8BitCompany for other prices. Ask about Sk prices for your sure too!

Hardware                                     Prince in Sk
MB-02 (basic version with 128k SRAM)            4.290,-
  +128k SRAM (total 256k SRAM)                    720,-
  +256k SRAM (total 384k SRAM)                  1.320,-
  +384k SRAM (total 512k SRAM)                  1.930,-
Disk drive FDD 3.5" HD                            990,-
Cabel for connect FDD drives                      110,-
Master power suply (impulsed) for MB-02           770,-
Real-Time-Clock                                   610,-
A-mouse (for offer)                               550,-
Profi pack (MB-02,512k,2xFDD,cabel,source,RTC)  9.570,-
BS-DOS 400 - licence for 1 user                   210,-
DOS-SwapSystem 1.00 (file convertor)               99,-

The end

If you want to know anything more, write me, or ask me on IRC, nick Busy or Buso.
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