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Topic: If I need three USB ports and the rPi only has 2... (Read 1151 times)

legendary
Activity: 1064
Merit: 1001
I hope you either mean 1.5A or 1500mA Cheesy
I do lol
hero member
Activity: 518
Merit: 500
Hodl!
I hope you either mean 1.5A or 1500mA Cheesy
legendary
Activity: 1064
Merit: 1001

I know some well back power the Pi with the usb port, I know some have let the magic smoke out of the Pi doing this.  A quality usb hub well not allow back power through the port.  Power from the usb port is not fused, zero protection.

Big surprise the first I tried to "reboot" my rPi with AMs! Unplug the pwr microUSB and still working haha Roll Eyes
My Pi will be getting it's power from a 1.5ma wall wort, the only USB connections it will have from he hub are from those small house looking ports witth the flatt roof if ya follow me lol.
member
Activity: 73
Merit: 10

I know some well back power the Pi with the usb port, I know some have let the magic smoke out of the Pi doing this.  A quality usb hub well not allow back power through the port.  Power from the usb port is not fused, zero protection.

Big surprise the first I tried to "reboot" my rPi with AMs! Unplug the pwr microUSB and still working haha Roll Eyes
member
Activity: 70
Merit: 10
If you forgot the USB stands for UNIVERSAL SERIAL BUS. So you cannot say that one brand or the other is the "recommended" for the rPi. Also the main issues on the USB Miners are the cord and the power supply. If you are using a dirt cheap and long cable, you will have a problem. If you have a good power supply to power the hub, make sure you have a high quality usb cable. And that is up to your budget also.  Cheesy

There is a "recommend" usb hub list put out by the Pi foundation.  The Pi has very basic usb 2.0 support.  The usb wifi warts have better performance when plugged into a powered hub, the Pi's port just does not supply enough power sometimes.  I would not use the Pi's port to power anything, keyboard and mouse only.


I have used the following hubs with the Pi.
D-Link 7 port, 3 amp psu runs 5 OK sometimes 6.
Rosewill RHB-500, 10 port, 4 amp psu, runs 8 OK.  I run 8+ a fan OK.
Rosewill RHB-520, 10 port, 3.5 amp psu, runs 7 OK.
Block Erupter, 49 port, runs from atx psu.  I'm using a cheap Apevia as520w atx psu, powers all 49 ports and gives excellent hash rate, I get 16.5Gh/s

I have had up to 60 miners on a single Pi but I would see a increase in rejects and hw errors.  I keep rejects under .3% and errors under .8%.  If you see less than the 333 hash rate it means you are not supplying enough power.  More than 20 miners bfgm seems to work better than cgm.

YMMV

Quote
-Be carefull with "plug in-plug out" of USB. rPi also gets powered from the USB ports, no only the microUSB.
-Don´t feed the PWR to the rPi from the same HUB you are using for miners.

I know some well back power the Pi with the usb port, I know some have let the magic smoke out of the Pi doing this.  A quality usb hub well not allow back power through the port.  Power from the usb port is not fused, zero protection.
member
Activity: 73
Merit: 10
I already have a powerd hub in mind I want to use that works with the Pi but it takes two USB ports to interface. I was thinking o using a y splitter on one of the rPi ports and the other or the wifi thing hence this question.

Advice for good performance, less HW errors, and longlasting devices:
-No usb splitters
-No chained usb HUBS (pwrd, not-pwrd)
-Attach WLAN dongle directly to the Pi (my advice on this will be Wi-Pi dongle).
-Be carefull with "plug in-plug out" of USB. rPi also gets powered from the USB ports, no only the microUSB.
-Don´t feed the PWR to the rPi from the same HUB you are using for miners.
-If you look for a wireless Keyboard/Mouse set for rPi I would recommend Logitec MK220. Durable, compact, and works perfection with the rPi without any install.

PD: I´ve made more or less the same setting few months ago so you can figure how many hours took me to figure all those things  Tongue
legendary
Activity: 1064
Merit: 1001
OIC
so those are actually 2x 10 port devices
I think you are going to have to sacrifice one of them for your wireless ..... or daisy chain one from the other - why not just use the wired ethernet on the RPi ?
Well this is what I was thinking which should work.

1st rPi port: Wireless Edimax thing.
2nd rPi port: http://www.ebay.com/itm/200965093125?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

Then in that splitter I can add the two USB cables form hat hub, and as you said which I confirmed a few minutes ago. It's actually a 2 x 10 port hub setup.

As for wired ether, I just don't want to use more cables than I need to... my room already looks like a noc cener with wires lol.
hero member
Activity: 792
Merit: 1000
Bite me
OIC
so those are actually 2x 10 port devices
I think you are going to have to sacrifice one of them for your wireless ..... or daisy chain one from the other - why not just use the wired ethernet on the RPi ?
legendary
Activity: 1064
Merit: 1001
...i but it takes two USB ports to interface. ...
WHAT?
post a link to this thing please
20 port hub on eBay, I've talked to a few people that say it works fine with the Pi iff you get a better brick for it. You can't see it from the imagges listed in the listin bu it interfaces with two USB cables. I assume you could get by with one but I wouldnt know.

http://www.ebay.com/itm/151155337245?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649#ht_1188wt_1170

As for powering the Pi, I'm gonna be using an wall charger thats 1500ma.
hero member
Activity: 792
Merit: 1000
Bite me
...i but it takes two USB ports to interface. ...
WHAT?
post a link to this thing please
legendary
Activity: 1064
Merit: 1001
I already have a powerd hub in mind I want to use that works with the Pi but it takes two USB ports to interface. I was thinking o using a y splitter on one of the rPi ports and the other or the wifi thing hence this question.
hero member
Activity: 518
Merit: 500
Hodl!
^5 Matu, just the page I was thinking of, but temporarily blanked on how to get to it or where it was filed in my monster pile of bookmarks.
member
Activity: 73
Merit: 10
True.

You can find it here:

http://elinux.org/RPi_Powered_USB_Hubs

Pay attention on Power Rating, and allways think about the future needs, not only for now. Also don´t forget to choose a "paralel" usb plug disposition because of space saving.
hero member
Activity: 518
Merit: 500
Hodl!
Although you'd think all hubs would be the same, there are some that don't like the Pi or vice versa, there's some pages/wikis around on the web with listings of "good" and "bad" hubs.

So if you're spending cash, googlum, if you've got half a dozen lying around, try them out.
sr. member
Activity: 364
Merit: 253
If you forgot the USB stands for UNIVERSAL SERIAL BUS. So you cannot say that one brand or the other is the "recommended" for the rPi. Also the main issues on the USB Miners are the cord and the power supply. If you are using a dirt cheap and long cable, you will have a problem. If you have a good power supply to power the hub, make sure you have a high quality usb cable. And that is up to your budget also.  Cheesy
hero member
Activity: 792
Merit: 1000
Bite me
99% of powered hubs will be fine,
just make sure it has a good PSU
you can use it to power the RPi also so you only have one wall plug
newbie
Activity: 4
Merit: 0
Hey. From what I remember when looking at the Pi, there has to be a list somewhere of certain brands/models of externally powered usb hubs that are actually recommended for raspberry Pi. I guess a simple random usb hub might have power issues if not incompatibility but one can always try!
sr. member
Activity: 364
Merit: 253
Powered USB Hub costs at around $10 only. So you should have one.
hero member
Activity: 792
Merit: 1000
Bite me
use a POWERED USB Hub
legendary
Activity: 1064
Merit: 1001
If I need three USB ports and the rPi only has 2, can I use a splitter on one o the rPi ports ?

Basically it's one port for a wifi thing and two ports needed or a hub setup.
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