GMX from Scorpio

Another version of GMX. Work continues!

Graphic Memory eXpander (GMX)
I/O ports
Working version as of 01/11/98

All ports work only for writing (port xxFF - reading).

xxFE Border port
D0 - G
D1 - R
D2 - B

xxFF Screen attributes port (only read)

7FFD Configuration port
D0 - SYS0
D1 - SYS1
D2 - SYS2
D3 - SCR
D4 - ROM1
D5 - BLKPK1

1FFD Expansion port
D0 - BLK1
D1 - ROM2
D2 - TRDOS - 1 - forced selection ROM TRDOS
D3
D4 - SYS3
D5
D6
D7

7EFD Mode port
>This is new
> D0 - EWR - write resolution in 28F400
> D1 - Vpp - enable programming voltage on 28F400
D2 - Normal/Turbo (0/1)
D3 - Graphic 256*192 / 640*200 (0/1)
D4 - A16 - A16 address on 28F400
D5 - A17 - A17 address on 28F400
D6 - A18 - A18 address on 28F400
D7

DFFD eXpanded Memory Port (Profi)
D0 - SM0
D1 - SM1
D2 - SM2

78FD 2nd window port (#8000-#BFFF)
D0 - SW0 SYS0
D1 - SW1 /SYS1
D2 - SW2 SYS2
D3- SW3 SYS3
D4 - SW4 SM0
D5 - SW5 SM1
D6 - SW6 SM2
D7

7AFD Scroller port ml. byte (8 bits)
DO - ml. bit
...
D7 - st. bit

7CFD Scroller port st. byte (6 bits)
D0 - ml. bit
...
D5 - st. bit

xx00 Global settings port
D0 - CONF0
D1 - CONF1 - FLEX8000 configuration option
D2 - CONF2
D3 - RECONF - write 1 + CONF0..2 - FLEX reboot
D4 - STR - 1 includes 64K ROM with standard firmware:
force install A16=1,A17=0,A18=0
D5 - BLKEXT - 1 blocks all new GMX ports, i.e. it turns out
the original SCORPION ZS265 Turbo+
D6 - BLKEX2 - 1 blocks all xxFD ports, 7FFD is addressed by FD,
in this case it is necessary to connect a ROM with standard
firmware (D4=1)
D7 - ST/PENT - standard signal generation INT (at the end
KS)(0) / as in PENTAGON (at the beginning of KS) (1)

ROM firmware map

#00000 - #01FFF - GMX startup bootloader which then transfers
control to address #40000,
#02000 - #03FFF - FLEX startup configuration at power-up,
#04000 - #0FFFF - 6 moreFLEX configuration options,
#10000 - #1FFFF - Standard firmware (48+128+TRDOS),
now TESTGMX (TESTSC+Graphic+2MB Memory)
#20000 - #3FFFF - Free for now
#40000 - #7FFFF - Scorpion V4_02 (256K)

ZY Please, no quarrel between us and the Peters! We have very good relations with them.
We are moving on an almost parallel course, but they are developing a completely new
board, and we need to provide improvements to thousands of our regular
customers. Because people who bought Scorpio 2-3-4 years ago, and gradually
bought up peripherals, are unlikely to give it up!

ZYY Peters! It's time to settle down on something! Otherwise, you already have some kind of Amiga
it turns out :).

PPPS IMHO 4MB of memory without a hard drive may not justify themselves, and attempts
to bring compatibility with the ZX Spectrum closer to 100% can lead to
a significant increase in cost.

Ironworkers of all countries unite!
Push lamers (or teach)!
Bye... bye bye, Sersh !