ZX-News #39 18 августа 1997

Железо

Controller SMUC - Istroriya creation.

             Controller SMUC


  In recent years, an increasing number of
spektrumistov equip their machines
hard disks. Already, most likely, to any type of Spectrum 
developed hardware and software support for hard drive with a 
single standard can be traced only in the type of interface - 
IDE, or E-IDE. But, as the results of my polls in the network 
SpbZxNet, in St. Petersburg, the vast majority of

users have the Scorpion ZS 256. Your
servant, too, has this car.


  Typically, when you connect a hard
drive to the Speccy the developers are two problems: the 
development of interface (Controller) and how to access the 
hard disk space. If the first problem is relatively easily 
solvable, then the second problem can be solved only partially. 


  The main cause of this problem is
System TR-DOS, which was developed
for floppy disks. The system does not
allows you to record to disc more than 128 and
files in the system there is only one directory, and a simple 
user can have access to only a 640-m kilobytes of memory. 
Therefore, in this direction would cost to develop a new DOS, 
which would satisfy all requirements of modern Spectrum'ov.

But ... Too many programs written
for the current TR-DOS, and their adaptation to the new disk 
operating system has taken would be very time consuming.



  Much faster to adapt the hard
drive to the TR-DOS. This problem is very
simply managed the company "Scorpion '
MOA ": hard drive space is divided into subsections, and 
subsections - it is collection of disks, each of which has

size is 640 KB.


  IS-DOS system more suited to
hard disk drive: it firstly,
can work with your device up to 16
MB, and secondly - the hierarchical system (in
like MS-DOS), ie in the root directory
You can create subdirectories, sub-directories, where files can 
be stored on different grounds, and nominations. Therefore any 
difficulties using this system on the hard drive usually does 
not arise. 


  Firm "Scorpion 'MOA" developed a universal controller SMUC. 
Stands for the abbreviation as Scorpion 'MOA Universal 
Controller. It is intended to connecting various IBM-periphery

CMOS-hours, etc., but above all it was designed as a hard disk 
interface. On-board controller and a chip NVRAM - nonvolatile 
memory capacity of 2 Kbytes, where you can save

various settings of the Shadow Service Monitor, the parameters 
of the hard disk, etc. 


  For the most successful and productive
the computer is desirable to connect
the controller to the computer Scorpion
ZS 256 Turbo +, although possible to work with
neturbirovannymi computers, as well as with
other Spectrum-compatible computers
(If the necessary modifications).
Software support for the controller is in ProfPZU computer 
Scorpion (volume - from 128 to 512 KB).



  Structurally, the controller is the PCB size 110h70 mm. 
Supply current controller, no more than 300 mA.