On Mon, Dec 22, 2014 at 02:56:54PM -0800, Keith Lofstrom wrote:
> On Mon, Dec 22, 2014 at 01:15:43PM -0800, Konstantin Olchanski wrote:
> > ...
> > Upgrading to new hardware depends on the depth of your pockets of course,
> > but we also see technical problems - some new 2GHz+ 64-bit SBCs overwhelm
> > power supplies originally built to run 0.1GHz motorola 68020 SBCs.
> > ...
> 
> No low power 64 bit SBCs?  This sounds like a market opportunity! 
>

Plenty of general purpose SBCs, not so many in VME form factor.

>
> Modern deep-submicron processes permit both very fast (Intel i7)
> and very low power (Atom) processors, the latter preferable when
> power and cooling is limited. 
> 

Hmm... would be interesting to see an Atom CPU run VME DAQ
at 40-60-100 Mbytes/sec over GigE...

>
> I am preparing a Zotac ZBOX small computer with SL7 for my wife's
> office; 64 bit dual core Atom, 5600 "bogomips", two displays,
> terabyte HD, 8 GB RAM ... all drawing 9 to 14 watts.  $220 for
> ZBOX and addons from newegg.  It has a cheap low-speed fan, but
> I can't hear it running.  Noctua.at makes the lowest noise fans.
> 

We are developing a CAMAC SBC using an ARM SoM
http://www.criticallink.com/product/mitysom-335x/
and a Cyclone4 FPGA. Electronics development cost, FPGA programming cost,
software programming cost is considerably higher than $220.

We are considering a VME SBC using an ARM+FPGA SoM
http://www.criticallink.com/product/mitysom-5csx/
but while really good on power and cooling, these ARM CPUs
cannot drive GigE at full GigE speed (memory is too slow).

>
> I don't know if an FPGA can drive a VME backplane, but those
> have evolved towards lower power per gate-MHz, too.  With
> all those extra gates, and live reconfiguration, a VME board
> could have BIST (built in self test) capabilities for on-line
> failure detection and debug.
> 

Most VME SBCs drive the VME bus using UniverseII and tsi148 PCI (*not* PCIe) to VME bridges,
but it looks like some vendors are moving to FPGA solutions. I have seen
at least one product announcement like this.

>
> If there is sufficient demand for a quiet low-power VME SBC
> replacement, I know consultants who can design one.  Bringing
> this back on topic, if it can be further optimized by kernel
> modules, I can think of a distro that could support them...
> 

The demand is not very high, and a good part of the demand is for "milspec" hardware
that has has "extended temperature range", "conductive cooling" and tested for vibration
tolerance.

-- 
Konstantin Olchanski
Data Acquisition Systems: The Bytes Must Flow!
Email: olchansk-at-triumf-dot-ca
Snail mail: 4004 Wesbrook Mall, TRIUMF, Vancouver, B.C., V6T 2A3, Canada