Re: Some discussion points open source friendly graphics [was: HARDWARE: Open-Source-Friendly Graphics Cards -- Viable?]

Timothy Miller
2004-10-29T15:47:19Z

linux-os wrote:
> On Wed, 27 Oct 2004, Daniel Phillips wrote:
>
>> On Monday 25 October 2004 18:45, Timothy Miller wrote:
>>
>>> My intention is to include a bit of logic in the FPGA which can be used
>>> to reprogram the prom. You would then cycle power to get the FPGA to
>>> load the new code.
>>
>>
>> Power cycle the whole machine, or software-reset the card?
>>
>> Regards,
>>
>> Daniel
>
>
> The FPGA requires a physical reset-pin toggle to load new
> bits into the gate-array. This could be software-toggled,
> but that would require at least one external gate. This
> is because the power-reset needs to reset the chip before
> its bits are loaded plus some pin, after loading, needs to
> be an output to its reset pin also. Therefore, you need
> the external gate that is always present.

Generally speaking, more chips == bad. If reprogramming the FPGA were a
regular event, I'd see the point, but I hope that MOST users would NEVER
have to reprogram it.