ColecoVision-on-a-chip (CV87) development log...

[opcode]

Hi guys!

 

Well, I officially started today development on my newest project, a ColecoVision-on-a-chip. If everything goes right, I will be following the roadmap bellow:

 

- Create a complete classic CV-on-a-chip. (2006)

- Release a CV-on-achip FPGA kit, complete with A/V outputs, cartridge slot, CompactFlash slot, joystick ports and an expansion port. (Q4/2006)

- Create a fully functional emulator of the SEM module (2006)

- Implement the SEM module in FPGA and release it as a free upgrade for the CV-on-a-chip, aka the CV87(2007)

 

So far I have started my SN76489AN (the CV sound IC) implementation. I am using VHDL, Xilinx Spartan3 FPGA and Xilinx ISE development tools.

VHDL is very interesting indeed, a bit strange in the first. Stuff isn't sequential like many software programming languages, but instead they are parallel most the time.

 

Considering this new direction, the originally planned SEM using off-the-shelf parts is no more. From my point of view it is even better, and I have now complete control of this thing again. Nothing is worst than depend on other people, cause they can or can’t be as motivated as yourself.

During the holydays I bought a DX7 synth to check how its FM generator works. I am planning to use FM synthesis with the SEM sound system, and IMHO nothing sounds more 80s than the DX7. In fact I found that the DX7 sounds a lot better than any commercially available FM IC from the 80s. Yamaha really kept theirs best toys exclusive…

 

 

I hope to post some news here soon...

 

Eduardo

[djmips]

Have you done any VHDL before? I haven't but I've always intended to learn.

 

Nothing is worst than depend on other people, cause they can or can’t be as motivated as yourself.

 

Now, I undestand this sentiment, it takes a special skill to organize a project and a good group of people, however it can and does happen. You may find that in your particular choice of projects it would be harder to recruit the caliber of cohort that's satisfactory.

 

Nevertheless, if you can't find a quality team and you are above comprimise, doing it all yourself is an attractive goal. And it's a hobby so even though it may take longer, you have no investors to cater too.

 

I agree with you on the DX7, I haven't looked but are there any DX7 emulators or VST instruments available and how do they compare?

 

Good luck on your hardware! I look forward to your progress reports.

[Pixelboy]

Hi guys!

 

Well, I officially started today development on my newest project, a ColecoVision-on-a-chip. If everything goes right, I will be following the roadmap bellow:

 

- Create a complete classic CV-on-a-chip. (2006)

- Release a CV-on-achip FPGA kit, complete with A/V outputs, cartridge slot, CompactFlash slot, joystick ports and an expansion port. (Q4/2006)

- Create a fully functional emulator of the SEM module (2006)

- Implement the SEM module in FPGA and release it as a free upgrade for the CV-on-a-chip, aka the CV87(2007)

995303[/snapback]

A question from someone who doesn't know anything about electronics (a.k.a. myself): Once the FPGA version of the CV-on-a-chip is done, could it be used as model for an ASIC design? Or does it need to be redesigned from scratch to optimize the ASIC version? (Sorry if my question doesn't make sense).

[Curt Vendel]

Are you aware this has already been done on MikeJ's site?

 

 

 

http://home.freeuk.com/fpgaarcade/cv.htm

 

 

 

 

 

Curt

[Pixelboy]

Are you aware this has already been done on MikeJ's site?

 

http://home.freeuk.com/fpgaarcade/cv.htm

 

Curt

1012279[/snapback]

Yeah, opcode is well aware of it.

[PacMan]

A question from someone who doesn't know anything about electronics (a.k.a. myself): Once the FPGA version of the CV-on-a-chip is done, could it be used as model for an ASIC design? Or does it need to be redesigned from scratch to optimize the ASIC version? (Sorry if my question doesn't make sense).

995358[/snapback]

 

Modern FPGA chips often contains embedded functions like RAM, Clock Managers etc. which makes life easy for the FPGA designer. Depending on your choice of ASIC manufacturer you may or may not find similar or identical functions for you to use in your design. So to answer your question, No you probably don't need to totaly redesign the VHDL model you created but it may need adaption to the ASIC libraries.

 

I know for instance that there are ASIC manufacturers that can take code written for Xilinx Spartan FPGA's and synthesize your code pretty much directly into their ASICs.

 

/P

[Bruce Tomlin]

Actually, a defining feature of FPGAs vs CPLDs is that all FPGAs have RAM. The RAM can be either used as the configuration for a logic cell, or as actual RAM. CPLDs use wired AND/OR gates for their logic functions, but FPGAs use tables in small groups of RAM cells (maybe 16x4 bits each).