Some years ago I work on ZX ULA clone:
http://velesoft.speccy.cz/cpld128ula.JPG
More tech information about ASIC I have on papers and in my head :) It's not so
hard for implement with modern hardware :) Some parts of ASIC clone projects
exist as my old sources, but I must all rewrite. Color palette will in external
sram memory, CPLD will contain only logic and paging ports. VL1772 can be
replaced later }with external coprocessor...
About ASIC code - I write all in ABEL language, it's not VHDL source. I will
rewrite all parts of ASIC to schematic for Eagle... after finish code. Source
development is very fast (some days/one week), and next time will used for
fixing bugs...
VELESOFT
----- Original Message -----
To: <[email protected]>; "VELESOFT"
Sent: Saturday, October 08, 2011 5:14 PM
Subject: Re: Resistor R55
Look forward to seeing more on this.
What status are you at with the ASIC module? Are you looking at
replacing the 1772 as well?
Any plans to make the ASIC code available - as it may allow others to
help with your development perhaps?
Quoting VELESOFT
----- Original Message -----
From: Leszek Chmielewski
To: [email protected]
Sent: Tuesday, October 04, 2011 11:11 AM
Subject: Re: Resistor R55
My SAM has no BRIGHT too. There was a shortcut between Composite and +12V,
so the MC1377P was burned out (Just got a replacement by desoldering a Atari
Mega STE), I lost BRIGHT too as the ASIC was toasted a little too. After
replacing it with ASIC from my spare SAM the BRIGHT is back again.
It is time to design a replacement ASIC. Velesoft is working on one since
years, but he is too ambitious: 4096 Colours, Hardware sprites and
scrolling...
LCD
Hi. My project is SAM COUPE clone (but no ASIC replacement). First prototype
will based on big CPLD + fast Z80cpu + big sram + saa1099 sound chip.
Here is components for first SAM clone:
http://velesoft.speccy.cz/other/ula-xc95288xl.jpg
http://velesoft.speccy.cz/IMGP3176.JPG
http://velesoft.speccy.cz/IMGP3178.JPG
Priorities:
- compatibility with SAM COUPE
- more colours (minimal 256 colors palette)
- faster CPU
- possibility run at full speed 6MHz in all graphic modes (not contended
memory)
- better compatibility with ZX Spectrum (ZX mode can work as ZX128)
- big ram + big rom
- internal peripherals...
Actuallly I must finish ZX projects: K-MOUSE 2011, complette RGB>VGA
convertor, ULA1 clone (zx clone based on old russian chil ULA1). After it I
can continue on SAM projects...
VELESOFT
