Raspberry Pi Compute Module 5 Is in Development

https://www.tomshardware.com/raspberry-pi/raspberry-pi-compute-module-5-confirmed-by-ceo-eben-upton

by WithinReason • 3 years ago

36 24 3 years ago

rocky1138• 3 years ago

Very happy to read that it uses the same form factor and connections as CM4 did. I was hoping we wouldn't even up with yet another socket.

jacquesm6• 3 years ago

I'd love to use these but the connectors are what has been putting me off. This is beyond my skill level.

dragontamer6• 3 years ago

I've never done it myself, but isn't the stacking connector just as easy as grabbing DF40HC(3.0)-100DS-0.4v (https://www.digikey.com/en/products/detail/hirose-electric-c...), throwing it into a KiCAD 2-layer or 4-layer board (depending on how complex you want to make it), and then just... that's it?

There's no RAM or other complex signals at play here. I have to imagine that 2-layer boards are sufficient for the vast majority of CM4 board users.

I guess a few elements in the connector (USB and Ethernet) are differential pairs. So okay, you need to know a bit about transmission line theory. But as far as actually running differential pairs with matched-impedances, its just a matter of knowing what a "dielectric constant" is and plugging that into the calculator, so that you know how thick the PCB-trace should be in a stripline.

Which is all nearly automatic even with free tools like KiCAD today. Okay, you need to know what the word "dielectric constant" is and that striplines are an impedance-controlled design pattern wherein the width of the PCB-trace on top is matched to a ground-plane below... and that you need the words "Dielectric Constant" and and "Board Thickness" to calculate the width for the impedance you're looking for.

But bam, now you know everything for simpler signals like USB or Ethernet. But honestly, whatever PCB you're designing is probably so small that it'd still work without needing to know any of this deeper theory.

supportengineer• 3 years ago

On a side note, when did this term "compute" work its way into the lexicon? "Compute nodes", etc. I don't recall this being a term until the last year or so.

jacquesm6• 3 years ago

With Plan 9 or so in the previous century?

dragontamer6• 3 years ago

Most supercomputer clusters are divided into compute-nodes vs management nodes. I'd have to imagine the language was popular as far back as the 1980s in the high-performance computing realm...

marcosdumay• 3 years ago

There are also IO nodes, that talk to disks and network.

Mainframes use those names too. I'm not sure what name blade hacks use (yeah, I'm out of a datacenter for that long), but they have those things too.

semi-extrinsic• 3 years ago

Supercomputers were not clusters like we have today until the mid-90's.

In the first written description of how to build a Beowulf cluster, by Radajewski and Eadline in 1998 [1], the management node was refered to as the "server node" and the compute nodes as "client nodes".

I believe the term "compute node" was first used in the context of the Intel ASCI Red supercomputer that was installed at Sandia in 1997. This later led to the Cray XT3, XT4, XT5 families of machines that used the same terminology.

But I believe the term was not in generic usage outside of those specific supercomputers until around 2005-2010.

[1] https://ibiblio.org/pub/Linux/docs/HOWTO/archive/Beowulf-HOW...

wharvle• 3 years ago

I don't recall ever seeing or hearing "compute" used as anything but a verb until several years into the rise of the "cloud".

emddudley• 3 years ago

I first noticed people referring to "compute" as a resource around maybe 2016.

declaredapple• 3 years ago

I've seen this a lot in contexts with specific workloads the last 10 years or so. With both physical space and PCIE lanes being factors, as well as how you handle virtualization/barebones setups. This can help with simplifying failover as well for HA.

For example, storage servers usually are full to the brim of harddrives and SSDs.

Then you might need to process your data on GPUs/CPUs where you have specific servers specced out with more CPU/GPU resources.

not_your_vase• 3 years ago

Compute Module on a platform that recommends active cooling? Excellent. Simply excellent.

postpawl• 3 years ago

Home Assistant yellow seems to have a pretty good solution, but it’s not currently active cooling for cm4. It’s a lot like a cpu cooler mount. Can see pictures here: https://www.jeffgeerling.com/blog/2022/home-assistant-yellow...

VikingCoder• 3 years ago

I want the 500...

Raspberry Pi Compute Module 5 Is in Development

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