PINE64

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cause i want to use one 1t usb hdd,if direct connect to pine64's usb it's not working.
i must use a powered usb hub now
so is there any way to increase usb current from 500ma to higher,
thanks a  lot.
(08-18-2016, 09:43 PM)listenfree Wrote: [ -> ]cause i want to use one 1t usb hdd,if direct connect to pine64's usb it's not working.
i must use a powered usb hub now
so is there any way to increase usb current from 500ma to higher,
thanks a  lot.

The correct way to increase the usb current is to use a powered hub; and make sure you have a good one that will not back-power (that is, it will not feed power back into the Pine board).

No, you cannot increase the available current on the usb port.
(08-18-2016, 09:43 PM)listenfree Wrote: [ -> ]so is there any way to increase usb current from 500ma to higher

Only on the 2 GB variants by setting a jumper you connect the power lines of the USB ports directly with DC-IN so an USB connected disk can draw whatever current it needs as long as you keep in mind that you have to avoid the Micro USB connector to power the board.

So using the Euler connector pins 4 (5V) and 6 (GND), switching from PMIC to DC-IN on the 2GB variant you can reliably use a bus-powered disk. Don't think about powering the board through Micro USB in this mode, the tiny contacts and the high cable resistance nearly all USB cables show will lead to voltage drops at disk spin-up which lead to the PMIC doing an emergency power-off of the whole board.
you mean when use dc-in,do not use micro usb at the same time.in this mode my ext usb disk may work?


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(08-29-2016, 07:02 AM)listenfree Wrote: [ -> ]you mean when use dc-in,do not use micro usb at the same time.in this mode my ext usb disk may work?

I don't think so.

http://linux-sunxi.org/Pine64#DC5V.2FBAT_POWER_jumper
(08-29-2016, 07:29 AM)tkaiser Wrote: [ -> ]
(08-29-2016, 07:02 AM)listenfree Wrote: [ -> ]you mean when use dc-in,do not use micro usb at the same time.in this mode my ext usb disk may work?

I don't think so.

http://linux-sunxi.org/Pine64#DC5V.2FBAT_POWER_jumper

I strongly recommend not, as the in the DC_IN mode, whatever power you have coupled to the Euler connector would feed back into whatever is providing power to the microUSB port... So with the jumper in the DC_IN position, you can still provide power via the microUSB, but due to the voltages losses on the connector, and the fact that USB can often be below 5v... powering via the euler connection is prefered, and will be more reliable in the long term.

@tkaiser: btw, ... both the 1Gb and 2Gb boards have the jumper.... I think its only the Pine64 512MB board that doesn't have the jumper, but both the Pine64+s do. And thanks for the test routine you posted on the other thread.
(08-29-2016, 07:56 AM)pfeerick Wrote: [ -> ]
(08-29-2016, 07:29 AM)tkaiser Wrote: [ -> ]
(08-29-2016, 07:02 AM)listenfree Wrote: [ -> ]you mean when use dc-in,do not use micro usb at the same time.in this mode my ext usb disk may work?

I don't think so.

http://linux-sunxi.org/Pine64#DC5V.2FBAT_POWER_jumper

I strongly recommend not, as the in the DC_IN mode, whatever power you have coupled to the Euler connector would feed back into whatever is providing power to the microUSB port...

Ok, I was referring to forget about this crappy Micro USB connector at all. Power through the Euler connector and you're done. So many problems people run into on boards that use this crap for providing power are only related to exactly this:  a crappy and horribly unreliable method to provide power limiting max current and ensuring voltage drops leading to all sorts of strange symptoms. On saturday I let OpenSSL 1.1 compile on Pine64+ powered through Micro USB and guess what: PMIC did an emergency shutdown in between.

Regarding the jumper, at least on my board (and maybe all early developer samples with the green led?) there is none: http://linux-sunxi.org/Pine64#Pine64.2B_.281_GB.29

It would be interesting whether the jumper appeared already on the first 1GB production batches or whether the Pine64 folks have released different 1 GB PCB revisions?
I just want my usb hd working without powered usb hub


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(08-29-2016, 08:24 AM)listenfree Wrote: [ -> ]I just want my usb hd working without powered usb hub

I sympathize with you;  but you probably cannot use your usb hd device without providing (additional) power. 

... If you're not powering directly with the euler bus (using a good filter) it isn't going to work at all without additional power;  and it probably is not going to work reliably in any case-- your usb hd draws too much power from the main board.  The solution is always additional power, usually in the form of a quality powered usb hub which does not backfeed. That's how I use my external hd;  why fight this problem ?
ok,thank you


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