Turbo 2+

* Message from gate SpbZxNet<=>FidoNet.

Hello Dmitry!

I wanted to write a little explanation
to the description of the TURBO 2+ ports, all this
was taken from a book (long since stolen
somehow [censored] from me). And also
going by the schematic diagram.

Well, here it is:

Ports:

The main system port that controls
the current configuration of the computer.

1.SYS_CS - port XX77h *

D0 - RG0
D1 - RG1
D2 - RG2

Switching screen modes, see below.

D3 - TURBO (3.5 MHz - 7 MHz)

Switching TURBO mode.

D4 - TON (not on the diagram)
D5 - TNAB (not on the diagram, although
is used in version 7.10, it
contains a trigger that removes INT from
the processor based on this signal)

D6 - AD/KEY
0 - IBM PC XT KEYBOARD
1 - ADC (ADC)

Sampling of what will be polled
through port 7D7Dh .

D7 - NMI reset (not shown in the diagram)

A8 - PEN

programming of the memory manager is enabled/disabled
through port XXF7h .
0 - disabled
1 - allowed

A9 - CPM

enable the CPM signal, for access
to TR-DOS ports from RAM (including
and TURBO 2+ system ports)

0 - active
1 - inactive

A14 - PEN2

0 - active CS FOR DSK_RAM & PAL_CS
1 - not active

Possible screen modes (controlled
using 1556ХЛ8)

ModeRG2&RG1&RG0

Sinclair 0 1 1
640x200 0 1 0
320x200 0 0 0
Text 1 1 0

2.PAGE_CS - port XXF7h *

memory manager

PAGE RAM OUTPUS

D0 - PAGE
D1 - PAGE
D2 - PAGE
D3 - PAGE
D4 - PAGE
D5 - PAGE

These six bits specify the number
of the connected page (ROM or RAM),
THE PAGE NUMBER IS INVERTED! In total
it is possible to connect up to 1 MB of RAM and
128 KB of ROM.

D6 - RAM

1 - RAM active,
0 - ROM active.

This bit indicates which
page is connected from RAM or ROM.

D7 - MX_A
1 - pages
from the standard Spectrum set are used 128
S128 PAGE_PORT 7FFDH , numbers 0 - 7

A14 - RAM SELECT1
A15 - RAM SELECT2

Set the page inclusion area

area A14 A15

#0000 0 0
#4000 1 0
#8000 0 1
#C000 1 1

Thus, through the memory manager
you can connect any page (ROM or
RAM) to any of the four areas accessible
to the processor.

* all actions with these ports
are performed only when the CPM signal = 0
i.e. either from TR-DOS ROM or from RAM,
but in this case you will have to activate
this signal manually, through port XX77h.

3.ADC/KEYBOARD DATA PORT - 7D7Dh

Poll of IBM PC XT keyboard or ADC,
selected in the system port, see above.

>4.MISCCONTROL READ PORT - 7FFDh
>
> D7 - ADC/KEY READY ( HIGH )
> D6 - HARD INT ( HIGH )
> D5 - TELEPHONE LINE is UP ( HIGH )
> D4 - BELL on TELEPHONE LINE ( HIGH )

This port is for reading, rather total
missing, because I didn’t
find it on the diagram.

Naturally, a bunch of ports remained
unlit, but I’ve already searched half the city
about that book
(Turbo 2+ operating and
setup instructions). And there are a lot of things there...:

pallet RAM ports,
hard drive ports, RS232 ports, ...

As soon as I find it right here.

By the way, did XPlayer7.8 reach you?

-+- zyasm
+ Origin: Creative Station - Best Station (812/03.00)