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The previous BeagleBoards also have a nice setup with a pair of PRU's (Programmable Realtime Units) that share memory with the main CPU. These MCU-like PRUs were leveraged in a lot of projects that needed external IO with low latency and high clock affinity, like audio processing, driving LED arrays, etc.

This Risc-V Beagleboard doesn't have anything like that. There are some entities in the space that are working towards that though...LowRisc.org has a concept of "Minion Cores".

The AM3558 (aka: Beaglebone Black/Green chip) looks like it is barely on the cusp of "doable" in KiCAD, though probably with some significant effort. Its an older chip but the fact that its ready to be laid out by an advanced hobbyist is very intriguing to me.

That being said: the latest chips from TI have significant improvements. PRUs always were wonky programs that were hard to grok. The more recent AM625 keeps the PRU for backwards compatibility (and buffs it up a bit), but IMO the on-board 400 MHz realtime Cortex-M4F is the more "obvious" realtime processor to use. Quad-Core Cortex-A53 should be plenty for most hobbyists as well.

Upgrading to DDR4 / LPDDR4 means tighter tolerances however, and the 441-pin (aka: 21x21 pins) AM625 probably needs 8-layers and maybe blind vias... while the older AM3558 (Beaglebone Black) can use DDR2 with much looser tolerances and only has 324 pins (aka 18x18). So 6-layers seems possible to me, maybe with a few pins disconnected.

Also, the main killer feature of both beaglebones and raspberry pis is long running mainline linux support and hardware availability. I am not so convinced this SoC is going to be around for that long.

it has a better chance than almost any other soc

You typically pay a premium for Beagleboards for the IO features (though at a glance this particular board doesn't look particularly interesting)

If you want an open RPi equivalent, I'd look more at LibreComputer boards. Cheap and open

Well, we're paying a premium for Beagleboards because they're lower volume and that's pretty much it. Volume is king for prices in the computer world.

But... you get better IO yes, but also more importantly IMO, more open hardware designs. Ex: I'm pretty confident in being able to get an AM355x TI chip and (with enough effort on a PCB CAD tool) creating my own Beaglebone Black/Green. (Note that OSHPark offers 6-layer boards which should be good enough to route-out impedance controlled DDR to a BGA chip like the AM355x series... though it'd be tight).

BeagleBone AI and BeaglePlay have upped the complexity so I'm not sure if they'd fit on 6-layers, but they're open-enough designs that if I were to create a custom 8-layer or 10-layer run, it probably is doable.

if you want to make your own boards I'd suggest looking at the Breadbee

https://news.ycombinator.com/item?id=36470660

https://www.cnx-software.com/2020/04/14/breadbee-tiny-embedd...

It's outside my area of expertise.. But I don't think making your own Beagleboard would be easy as you say.. At least I've not seen it done. Have you done that?

No, but I'm getting close to the point where I'll attempt it.

OSD335x is the SiP version with integrated DDR RAM, removing the most difficult part of PCB design (ie: impedance matched / delay matched DDR). It's more expensive than a raw AM3558 from TI, but it'd be my first step.

Then when I want to try the more difficult DDR routing, it's available and Beaglebone Black/green serves as reference designs for me to study.

> LibreComputer boards. Cheap and open

True. Unfortunately they're impossible to purchase outside of Amazon or at any EU shop that supports PayPal.

Yeah, they weirdly don't even have a Taobao shop.. so can't be bought in China as far as I can tell. It's a bit strange

They have an Aliexpress store that appears to ship from China: https://www.aliexpress.com/store/1102551393

Right, but Aliexpress doesn't do delivery in China! :))

(hard to believe, but it's true)

>BeagleBoards tend to be in the 1W to 5W region, while Rasp. Pis consistently are 5W+ (with the most recent Rasp. Pi even having a 20W+ adapter but probably averages at half that). RP4 averaging around 6W, so well above BeagleBoard stuff.

Please look at JH7110 instead, as it has much higher efficiency and draws much less power.

Boards include the VisionFive 2, Star64, Pinetab-V as well as Milk-V Mars.

>I thought that Beagle Company was more tied to TI chips than this, I didn't expect a non-TI chip to come out of their boards.

I would say it's simpler than that: TI failed to release a RISC-V chip in a timely manner, whereas BeagleV (correctly) identified the direction the industry is moving towards.

There was a "strong" product, the Beagleboard X-15. It came out before the Pi4 and had better performance than a Pi3B. However, it was on the expensive side at over $200.

Aren't there many ARM chips which are more efficient (compute per watt) and which also use much less power when idle than what the Raspberry Pi uses?

RP5 changes the specs again and I haven't bothered to run the math yet.

Broadcom / Rasp. Pi chips have historically been _VERY_ bad at idle though compared to their peers. So I think its safe to say that RP5 will also be bad at idle (though I haven't read the spec sheets or seen any such tests yet).

Seems a good guess. https://www.tomshardware.com/reviews/raspberry-pi-T;

“The Raspberry Pi 5 is the hottest of all the Raspberry Pi boards we have ever used. At idle, without any added cooling, it sits at around 50.5 degrees Celsius and consumes around 2.7 Watts“

If that were classified as “electrical and electronic household and office equipment”, they could not legally sell that in the EU (https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=uriserv%... is not yet in force, but its predecessor already limit standby power usage to under 0.5W)

IANAL, but I think the right comparison for standby power usage would be the power usage in sleep, not in idle.

Yes, though I would say the beaglebone is also not stunning in this regard.