Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Vocore2, a ridiculously small Linux PC

vocore.io

Post reply on HN
Print view View original

31–40 of 70 posts

Re: Vocore2, a ridiculously small Linux PC

#31

Post by plasticchris »

gdfasfklshg4 wrote: post #30
logicallee wrote: post #26

Earlier quoted context omitted.

I looked at what you meant, and first found this article https://hackaday.com/2016/06/30/transcend-wifi-sd-card-is-a-... which links this article: https://jamesone111.wordpress.com/2014/03/19/exploring-the-t... So this is a Linux server in the size of an SD-Card that has 16 GB of storage. And Wifi. And lets clients connect to download whatever's on them. I was thinking, wow, this must be some pro photography thing co…

My experience is that SD-cards don't last very long when used as the `/` directory.

Use a read only root fs and overlays in ram, this will keep your sdcard based Linux server running much longer, though it is a bit tedious to set up.

Re: Vocore2, a ridiculously small Linux PC

#32

Post by rcxdude »

adiusmus wrote: post #10
etaioinshrdlu wrote: post #7

Related: The Octavo systems system-on-package: https://octavosystems.com/ It's a TI AMxx series linux computer in a package on package module like a raspberry PI is. It comes in two variants, a regular pitch BGA and an ultra wide BGA so that it is actually possible to hand solder it! (or with hot air or a toaster.) It is what is used on the Pocket Beagle. It saves you the need to to most high speed signals and really…

Nice spec. 2x Ethernet?! Custom router possibilities abound. More expensive than Pi however. I can get an entire pi for the same price as this module,

The 2x Ethernet is a little quirky in implementation: Internally, the CPU only has one ethernet MAC, which is connected to a switch on the same die. In practice, linux sees two ethernet ports, but this is implemented by VLAN tagging on the internal switch. So if you think you have two actual ports and want to interact with VLANs, you're gonna have a bad time.

Re: Vocore2, a ridiculously small Linux PC

#33

Post by rcxdude »

amelius wrote: post #17

The problem with Linux in these applications is that it's not a realtime OS.

You can get pretty fantastic latencies on stock linux with some tuning, with the kind of processors embedded linux runs on you only really gain some microseconds by going to realtime variants. The main reason to prefer a true RTOS is because it will generally be simpler, and thus a bit more predictable and reliable in its behaviour, which is important for high-reliability systems.

Re: Vocore2, a ridiculously small Linux PC

#35

Post by giancarlostoro »

caccialdo wrote: post #25

Website says: "It will help you to make [...] the tiniest router in the world." Got one of these and I'm pretty sure they're quite smaller: http://amzn.asia/d/idyKhjN Makes me wonder if I could turn those Japanese routers into computers (they're dirt cheap at £8.50)...

TP Link has the N300 available too, powered by USB Micro:

https://www.amazon.com/TP-Link-Wireless-Portable-Travel-Rout...

Only downside is they're $29.

Re: Vocore2, a ridiculously small Linux PC

#36

Post by awvcs »

rcxdude wrote: post #32
adiusmus wrote: post #10

Earlier quoted context omitted.

Nice spec. 2x Ethernet?! Custom router possibilities abound. More expensive than Pi however. I can get an entire pi for the same price as this module,

The 2x Ethernet is a little quirky in implementation: Internally, the CPU only has one ethernet MAC, which is connected to a switch on the same die. In practice, linux sees two ethernet ports, but this is implemented by VLAN tagging on the internal switch. So if you think you have two actual ports and want to interact with VLANs, you're gonna have a bad time.

And the performance isn't very good either from what I have heard. It is a good candidate if you want to try and make something cheap, but few (none?) of the offerings really are (olimex has one if anyone is interested). Personally I am pretty tired of the Linux ecosystem in general. It is pretty well known that you can ship broken stuff by slapping an open source sticker on it.

Re: Vocore2, a ridiculously small Linux PC

#37

Post by cordite »

voltagex_ wrote: post #4

I'm pretty sure I gave away my original Vocore - the pins were simply too small for me to solder. The Vocore2 looks like a considerable step up, but without mainline Linux support it's of limited utility.

Ditto on the pin size. I wasn’t able to find utility out of it

Re: Vocore2, a ridiculously small Linux PC

#40

Post by squarefoot »

stereo wrote: post #21

I have one from the original crowdsourcing campaign, with an audio dock. Interference makes the sound quality is so bad it's unusable for any practical purposes. Support was useless. http://forum.vocore.io/viewtopic.php?f=16&t=3500&p=5185

HappyAlbatross is right: you definitely have a grounding problem, either due to missing proper ground or having a ground loop somewhere. Also if you're using a switching power supply and/or a class D amplifier (that is, a switching amplifier [1]), they can be real nightmares if not properly filtered, and cheaper ones almost never are. Grounding and ground loops, filtering and decoupling are complex issues which would need entire articles, but there's a lot of stuff on the net to get you started. Long story short: don't throw away your board, the problem could disappear just by changing a power supply or rewiring ground connections.

[1] They use the same identical principle behind switching power supplies but applied to driving speakers: performance is fantastic compared to current draw, but they tend to produce lots of harmonics and RF noise just like switching power supplies.

Post reply on HN