[Arm-netbook] parallella

[Dr. David Alan Gilbert]

* 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 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).
> 
> > 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.

Dave
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