MSD #03 12 июня 1999

Программирование     Scorpion ZS

Iron - Scorpion ZS 256: a quick guide for programmers.

  SCORPIO ZS 256, QUICK START GUIDE FOR PROGRAMMERS
 This material is published purely iformatsionnoy point of view,
unfortunately still some owners SCORPION'ov
(A Ufa of the majority) do not possess this information.
1.1 ALLOCATION OF I / O Ports
1.Port 7FFDh (32765): Fully compatible with your computer
 ZX SPECTRUM 128. Sampling occurs at the port
a0, a2, a5, a12, a14 = 1; a1, a15, IORQGE = 0

  Nznachenie discharge of this port:

  D0-D2-specified number of pages of RAM to be included in the 
region C000h-FFFFh


  D3-switching RAM addresses start screen: 0-ZX128 ,1-ZX48

  D5 -1 in this bit blocks the further conclusion to the port
 7FFD, until it reset. This usually occurs in the transition 
mode BASIC48 and need to turn off more memory. Appeal to the 
port 7FFDh can only occur at level of machine code. Record any 
information by the operator BASIC OUT will either reset or hang 
the computer. When using this port at the code necessary to 
prohibit the termination of the time change the content of this 
port. 2.Port 1FFDh (8189) - an additional port for management


  computer. xporta Sampling occurs when:

  a0, a2, a5, a12 = 1; a1, a14, a15, IORQGE = 0
Appointment of bits of this port:

  D0 - bit block ROM in the region 0-3FFFh; record 1 allows
writing and reading of zero page RAM.

  D1 - select ROM Expansion (using PZU27512) in this ROM

  is the main part of the informal service monitor

  D2 - used to display on the RS-232C

  D3 - not used

  D4 - expansion RAM zapis1 - connects to the region C000h-FFFFh
page of RAM with a number from 8 to 15. Specific page number
determined by the bits D0-D2 port 7FFDh.

  D5 - strobe signal to the interface CENTRONICS, to form the 
necessary software to form a gate in the single pulse 
discharge. 

  D6 - not used

  D7 - not used

  When you reset all bits of port 1FFDh set to "0".

  Appeal to this port can only occur at the level of
machine kodov.Zapis any information by the operator
BASIC OUT lead either to discharge or to hang companies. An 
exception is the management of discharge D2, D5. 3.PORT 
0FFh-port current attributes screen. 

  Sampling port occurs at a0, a1, a2, a5, DOS / = 1; IORQGE = 0

  When reading from a port 0FFh shall enter into the CPU values
attribute of familiarity, which takes place on the map
display screen. If at the moment is reading a map
Border, then enter a value 0FFh.Te same data will be entered
in the CPU, if the command is executed to read from any 
non-existing port, ie, will not be selected any physical port 
or on board "Scorpion", nor on the boards periphery. This port 
is introduced into the motherboard of a computer to provide a 
more complete software compatibility with the ZX Spectrum 48. 
4.Port 0FEh (keyboards). 

  Sampling port occurs when a1, a2, a5, DOS / = 1; IORQGE = 0

  bits D0 ... D4-input keyboard

  discharge D5 - input tape,

  bit D6 - used to enter by RS-232C,

  pazryad D7 - used for signal analysis, "BUSY" interface

  "CENTRONICS".
5.Port for the printer (Centronics) - FFDDh (65,501).

  Sampling port occurs at a0, a2 = 1; a1, a5, IORQGE = 0

  In this port is write the character code, issued by
 printer.

  Possible to use this port for other purposes
 As Fringe output channel.
5.Porty musical coprocessor AY-3-chip 8912.Eta
contains 16 registers, chosen by
write register number to port 0FFFDh (65,533), and then reading
contents of this register at the same address, or writing the 
new contents of the selected register at 0BFFDh (49,149). 
Choosing number of the register once, you can then any number 
of times to write / read data to / from it. And just when you 
switch to another register is required to rewrite the contents 
of the port at 0FFFDh.

7.Porty system TR DOS. These ports are only available
in the transition to a system of TR DOS (signal DOS / = 0), 
with disabled ports for keyboard and screen attributes. 

  Sampling controller ports TR DOS occurs at a0, IORQGE,
DOS / = 0; bits a1, a5, a6, a7 define a specific port address.

  Port 1Fh-register command / status 1818VG93

  Port 3Fh-register paths 1818VG93

  Port 5Fh-Register sector 1818VG93

  7Fh-Port Data Register 1818VG93

  Port FFh-entry: the system registry TR DOS:

           D0 - drive number

           D2 - reset 1818VG93

           D3 - readiness

           D4 - the choice of a floppy disk

           D6 - a recording method (0-FM; one-MFM)

           Reading: the state of signals DRQ and INTRQ 1818VG93

           D6 - state of the signal DRQ (38 pin. VG93)

           D7 - state of the signal INTRQ (39 pin. VG93)

To answer your questions (if we can of course!), If the issues
many, tamp them and pass on a floppy diskette refund.

  (Yes, and not empty!)