Re: Apple II VGA Video Generator Card Project

["Henry" <apl2research@comcast.net>]

Hello Alex.

Could you please email me that section of the HDL code?  If you do plan on 
writing DHGR support, I wouldn't complain. ;-)  Save us some work. 
Soldering for us is also no problem either.

Email on this account is good.  Thanks.


Henry S. Courbis
www.GSE-Reactive.com
Apple II Series Legacy Hardware - Come take a look at what we have to offer!

"Alex Freed" <alexf@mirrow.com> wrote in message 
g_SdnX3BcN0xLmreRVn-pw@comcast.com">news:g_SdnX3BcN0xLmreRVn-pw@comcast.com...
>
> Great minds think alike :))
>
> I was going to mention that I already have Verilog that does a good job
> of showing standard Apple video on a VGA screen. I didn't do the double 
> hires, but it is quite trivial to add.
>
> So one simple way to do it is to put the smallest Spartan 3 or Altera 
> Cyclon FPGA on a card. It has everything: enough RAM for the frame buffer, 
> PLL to multiply the clock frequency and more than enough logic
> to do the job. XC3S50-4VQ100C costs $10. That's the good part. The bad 
> part is that soldering such chips is beyond hobbyist technology. At least 
> for most people. So it has to be done professionally.
>
> The beauty of the FPGA approach is that it is so flexible. You can always 
> add a new video mode or what have you at any time. The character generator 
> will also fit inside and can be re-programmed.
>
> On the other hand if you have an FPGA, why stop at video generation when I 
> have fitted the whole Apple 2 into it? And who needs accelerator chips if 
> I can run my "6502" at 28 MHz clock? Probably even faster if needed.
>
> Then again the VGA video card could be built with just TTL chips and GALs 
> or a CPLD. Easier to assemble but a lot more parts.
>
> BTW there is no need for dual ported RAM: 500 nS out of every 1 mS 6502 
> does not acess the memory. That's how the normal Apple video works. Using 
> modern SRAM it is trivial to read 4 bytes in 500 nS (double scan rate AND 
> double hi-res or 80 columns).
>
> I could make either a video for VGA or a whole FPGApple available 
> commercially if I new there was a market.
>
>
> aiiadict@gmail.com wrote:
>> http://www.mirrow.com/FPGApple/screenshots.html
>>
>> http://www.mirrow.com/FPGApple/
>>
>>
>> He's got apple II video displaying on a VGA screen, perhaps
>> the code can be modified to work with dual port RAM in
>> a real apple II
>>
>> Rich
>>