Сообщение от VELESOFT
ZX PROFI 1024 kB
port 7FFD: (adressation - 0xxxxxxx xxxxxx0x )
named on Profi CMR0
D0 = bank 0 ;128 kB memory
D1 = bank 1 ;128 kB memory
D2 = bank 2 ;128 kB memory
D3 = videoram **
D4*= rom (rom14)
D5 = disable paging
D6 = unused
D7 = unused
port DFFD: (adressation - xx0xxxxx xxxxxx0x )
named on Profi CMR1
D0 = bank 3 ;256 kB memory
D1 = bank 4 ;512 kB memory
D2 = bank 5 ;1024 kB memory
D3 = select the window in the address space for mapping memory pages
0 - adress C000 (ZX-Spectrum 128 standart);
1 - adress 4000 Then the address c000 will bank 07
D4 = disable rom and connect ram page 0 in adress space 0-3FFF
D5*=
0 - port addresses (1F, 3F, 5F and 7F) are used to access i8255A (KP580BB55)
1 - port addresses (1F, 3F, 5F and 7F) are used to access 1818WG93
D6 = if D4=1, 8000..C000 =page6 (pixels 512x240)
D7 = screen mode 512x240 (extended video mode used in CP/M)
(*) ZX-Profi 3+ (board ver 5.xx) unlike ZX-Profi (board ver 3.xx)
use extended address space which changed the port addresses of
the expanded peripheral devices.
Combinations of these bits select the list of available ports.
Ie choose a method of addressing.
1) rom14=0 addressing as a ver 3.xx. Bit D5(dffd) selects 8255 (0) or VG93 (1)
The rest of the extended peripherals are not available.
2) rom14=1 & D5(dffd)=0 Addressing as a ver 5.xx. Set accessible peripheral expansion ports:
i8253, i8251, hw clock (mc146818), IDE interface. i8255A &1818VG93 have their addresses and ports are available at the same time.
**
3) In the enhanced video mode (512x240) this bit so chooses display options:
= 0 - pixel page 06, attributes (for each byte pixels) - 58 (72 in octal)
= 1 - pixel page 04, attributes (for each byte pixels) - 56 (70 in octal)
And also if you set bit 4 in DFFD (CMR1), then register CMR0 unlocked.
Ie it cancels bit 5=1 CMR0.
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