Where are OCM clones?

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By dhau

Paragon (1570)

dhau's picture

05-01-2007, 14:52

With OCM Quartus project files available for public, I wonder when someone is going to adjust it for very similar, reasonably cheap and readily available TerasIC DE-1 motherboard?

DE1 pros (as opposed to OCM):

- almost twice the amount of logic cells (20K vs 12K);
- 4MB fast directly mapped on-board flash;
- 512KB super-fast SRAM;
- 80 generic I/O-pins;
- fast USB-Blaster direct FPGA configuration upload, as well as upload to serial config flash;
- fast reliable RS232 port;
- lots of debug/config things (switches, push buttons, leds, 4 alapha-numeric display etc);

DE1 cons (as opposed to OCM):

- doesn't look as nice;
- lacks glue CPLD to interface 2.5V Cyclone II FPGA to 5V slots/peripherials;
- no TV output, only VGA;
- less SDRAM (8MB vs 32MB, but do you really need all that RAM?);

Common features:
- VGA output (DE1 has 4-bits per each channel - max 4096 colors, max 640x480 @ 60Hz)
- SD slot;
- PS/2 keyboard/mouse port;
- USB i/o;
- audio out/in/mic.

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By Bastiaan

Champion (333)

Bastiaan's picture

05-01-2007, 15:04

nice specs, but how to connect an MSX cartridge?

By dhau

Paragon (1570)

dhau's picture

05-01-2007, 15:12

No way, without extra hardware. Basically you need a proto-board with two MSX-slots, one of the cheapest 5V tolerant CPLDs to interface 5V to 3.3V signal levels (Cyclone II is 2.5V device, but is 3.3V tolerant). Not 100% sure how to handle analog audio pin on MSX cart. Probably just mix sound output from DE1 and sound pin through 2 resistors (analog mixing). But then again, why bother if you have SCC, MSX-Audio and MSX-Music in FPGA?

By syntax_error

Resident (51)

syntax_error's picture

05-01-2007, 22:28

You're a retro-nut... which geek isn't? The baby is born!

http://www.8bitbaby.de/

By dhau

Paragon (1570)

dhau's picture

06-01-2007, 03:08

I'm not sure what you mean with the link above. If you refer me to C-One project, it's just a piece of obscenely overpriced, underpowered and outdated hardware.

On a related note, friends from zx.pk.ru/ told me how to interface 5V devices (such as real cartridges, Z80, AY/YM etc.) and Cyclone II. You have to use 74ACT or 74HCT series buffers and power them with 3.3V. They will recognize 5V level inputs and provide 3.3V outputs. Cyclone II is, fortunately, 3.3V tolerant.

By cax

Prophet (3738)

cax's picture

29-05-2007, 07:51

Check here and here.

By NapalM

Master (234)

NapalM's picture

29-05-2007, 12:58

I have a C-ONE (http://c64upgra.de/c-one/) and, and is the UNLESS HARDWARE EVER!
to load software you NEED an original commodore disc drive T_T,I have not been able to never use it with an disk image.

Oh, "only" "emulate" C64, vic20 and amstrad, no msx, no spectrum... ( "Emulate" c64 , the harware use an REAL c64pcu, a REAL SID chip and a REAL disc drive...only "emulate" the...motherboard...)
a very strange hardware....is veeeeeery beta....yet

By cax

Prophet (3738)

cax's picture

29-05-2007, 13:11

>UNLESS HARDWARE EVER!

You mean "USELESS" ?

By NapalM

Master (234)

NapalM's picture

29-05-2007, 13:51

uhm...uhh...... r..s..t..u...use...usele.... useless!... yes Smile

By TobiFlex

Supporter (8)

TobiFlex's picture

29-05-2007, 23:57

I invested much time into the C-one. And you call it "useless". I am very sad.
TobiFlex

By NapalM

Master (234)

NapalM's picture

30-05-2007, 09:42

When the C-ONE can load disk images correctly , it will be a useful machine, while it requires original old harware original, is not.

I have not been able to load cpc disk images either.

If I cannot load software, I cannot use the machine, is useless.

Sorry.

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