<p dir="ltr">I've got one of these.<br>
Among other things it lets me power an external hdd.<br>
<a href="http://www.cnx-software.com/2013/12/21/x100-raspberry-pi-expansion-board-adds-vga-output-rtc-and-more/">http://www.cnx-software.com/2013/12/21/x100-raspberry-pi-expansion-board-adds-vga-output-rtc-and-more/</a></p>
<p dir="ltr">Alternatively make sure when you get a powered hub it does not backfeed in to the pi. You might need to disconnect pin +5V on the usb cable between the pi and the powered usb hub.</p>
<p dir="ltr">Guy</p>
<div class="gmail_quote">On Dec 15, 2014 1:37 AM, "E.S. Rosenberg" <<a href="mailto:esr%2Blinux-il@g.jct.ac.il">esr+linux-il@g.jct.ac.il</a>> wrote:<br type="attribution"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div><div><div><div>Raspberry Pi uses USB2.0, it can't provide enough current to big peripheral devices full stop.<br></div>It's so bad that plugging in a disk-on-key while it's running can cause a sufficient voltage drop to reboot the system (after which the d-o-k will work).<br></div>That's why you need to have a powered USB hub, USB3.0 allows more power to flow through the ports so it will be more efficient with ports (with USB2.0 external HDDs of the 3,5" variety tend to have a second USB connector to get extra current).<br><br></div>HTH,<br></div>Eliyahu - אליהו<br></div><div class="gmail_extra"><br><div class="gmail_quote">2014-12-14 22:41 GMT+02:00 Amos Shapira <span dir="ltr"><<a href="mailto:amos.shapira@gmail.com" target="_blank">amos.shapira@gmail.com</a>></span>:<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr">Get a powered USB hub (i.e. a usb hub which also connects to a wall power socket). I'm not familiar with RPi USB version but check for USB 3.0 vs. 2.0.<div class="gmail_extra"><br><div class="gmail_quote"><div><div>On 15 December 2014 at 06:07, Gabor Szabo <span dir="ltr"><<a href="mailto:gabor@szabgab.com" target="_blank">gabor@szabgab.com</a>></span> wrote:</div></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div><div><div dir="ltr">Hmm, good question. The Raspberry does see the device when it is connected, so is it possible that it needs more<div>power after later on?</div><div><br></div><div>How can I check?</div><div><br></div><div>If the problem is lack of current, how can I solve that? Can I put one of these usb hubs that also provide power between the two?</div><span><font color="#888888"><div><br></div><div>Gabor</div></font></span><div><div><div class="gmail_extra"><br><div class="gmail_quote">On Sun, Dec 14, 2014 at 8:43 PM, E.S. Rosenberg <span dir="ltr"><<a href="mailto:esr+linux-il@g.jct.ac.il" target="_blank">esr+linux-il@g.jct.ac.il</a>></span> wrote:<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr">Are you providing the external HDD with sufficient electricity? The Raspberry is most likely not capable of providing enough current...<br></div><div class="gmail_extra"><br><div class="gmail_quote"><div><div>2014-12-14 19:30 GMT+02:00 Gabor Szabo <span dir="ltr"><<a href="mailto:gabor@szabgab.com" target="_blank">gabor@szabgab.com</a>></span>:</div></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div><div><div dir="ltr">So finally I install the Raspberry Pi I bought a few weeks ago and wanted to add an external HDD.<br>I plugged in the external hard drive and /var/log/syslog printed the following:<br><br><br>Dec 14 17:02:55 pi kernel: [ 759.981949] usb 1-1.3: new high-speed USB device number 8 using dwc_otg<br><br>Dec 14 17:02:55 pi kernel: [ 760.<a href="tel:163364" value="+61163364" target="_blank">163364</a>] usb 1-1.3: New USB device found, idVendor=1058, idProduct=0820<br><br>Dec 14 17:02:55 pi kernel: [ 760.<a href="tel:163398" value="+61163398" target="_blank">163398</a>] usb 1-1.3: New USB device strings: Mfr=1, Product=2, SerialNumber=5<br><br>Dec 14 17:02:55 pi kernel: [ 760.<a href="tel:163414" value="+61163414" target="_blank">163414</a>] usb 1-1.3: Product: My Passport 0820<br><br>Dec 14 17:02:55 pi kernel: [ 760.<a href="tel:163429" value="+61163429" target="_blank">163429</a>] usb 1-1.3: Manufacturer: Western Digital<br><br>Dec 14 17:02:55 pi kernel: [ 760.<a href="tel:163444" value="+61163444" target="_blank">163444</a>] usb 1-1.3: SerialNumber: 57583431413432454363833<br><br>Dec 14 17:02:55 pi kernel: [ 760.<a href="tel:169522" value="+61169522" target="_blank">169522</a>] usb-storage 1-1.3:1.0: USB Mass Storage device detected<br><br>Dec 14 17:02:55 pi kernel: [ 760.181935] scsi0 : usb-storage 1-1.3:1.0<br><br>Dec 14 17:02:56 pi kernel: [ 761.183065] scsi 0:0:0:0: Direct-Access WD My Passport 0820 1012 PQ: 0 ANSI: 6<br><br>Dec 14 17:02:56 pi kernel: [ 761.187365] scsi 0:0:0:1: Enclosure WD SES Device 1012 PQ: 0 ANSI: 6<br><br>Dec 14 17:02:56 pi kernel: [ 761.189473] sd 0:0:0:0: [sda] Spinning up disk...<br><br>Dec 14 17:02:56 pi kernel: [ 761.277106] sd 0:0:0:0: Attached scsi generic sg0 type 0<br><br>Dec 14 17:02:56 pi kernel: [ 761.278094] scsi 0:0:0:1: Attached scsi generic sg1 type 13<br><br><br>But then when I try to run<br><br><br>$ sudo fdisk /dev/sda<br><br>I get<br><br>fdisk: unable to open /dev/sda: No such device or address<br><br>$ ls -l /dev/sda<br><br>brw-rw---T 1 root floppy 8, 0 Dec 14 17:21 /dev/sda<br><br>$ sudo fdisk -l<br><br>only lists the sdcard<br><br><br>The external disk is brand new and it has NTFS on it. I have not handled disk in linux for a long time, but a I recall I am supposed to use fdisk to partition it and then use mkfs.ext4 to format.<br><br><br>So what am I missing here?<span><font color="#888888"><br><br><br>Gabor<br><br><br></font></span></div>
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