[Arm-netbook] parallella

[luke.leighton]

On Sat, Jul 27, 2013 at 6:32 PM, Dr. David Alan Gilbert
<dave at treblig.org> wrote:
> * luke.leighton (luke.leighton at gmail.com) wrote:
>> On Sat, Jul 27, 2013 at 5:20 PM, Dr. David Alan Gilbert
>> <dave at treblig.org> wrote:
>>
>> > ...and keep the frame buffer up to date - not sure what the bandwidth
>> > is like, and what the mapping to the main memory is like.
>>
>>  the parallella is already doing a framebuffer by reading the DDR3 RAM
>> and pushing that out to a parallel-bus-to-HDMI converter IC.  DDR3 @
>> say 800mhz is more than enough to keep up with the 370mbytes/sec
>> needed for 1080p60.  sounds extreme but it's only 12% of the 800mhz
>> DDR3 memory bandwidth budget.  1080p30 is 6%.
>
> Right, but it's the Zynq doing the framebuffer, not the epiphany

 yes.

>as
> I read it; so is there the bandwidth from the framebuffer/dram to make
> the epiphany work as a GL layer well? (Reading the manual it's got about
> 1.5GB/s which I guess is just OK depending how it works).

 *clueless*

>>
>> > Now what about storage?
>>
>>  i believe it's SPI NOR flash, on the parallella.
>>
>> > PCIe or SATA or something in the FPGA - is there
>> > the space to do that and everything else needed?
>>
>>  it's not a space issue - the 7010 and 7020 don't have the fast lane
>> LVDS needed, so it's a non-issue.  you'd have to go to the 7030 or put
>> down a JM20329 and a USB hub IC.  which is ok.  not great, but ok.
>
> Hmm ok, so yes the 7030 looks nice; claims Gen2x4 PCIe, and 2xGigE (whether
> you can have those at once I don't know).....but only £252 at Digikey. Oh.

 yeeek!   they're supposed to be reasonably priced!