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Power drain

What with a change in set-up when moving house, I no longer have access to an HDMI screen so bought an HDMI to VGA converter and hooked up a spare LCD monitor. I am pleased to say this works well and (using RISC OS) I am looking at a 1280x720 screen. Yay!

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As a bonus, this item includes a mini-jack lead, though this has to be between the Pi and an amp, not the outlet on the converter and the amp.

Unfortunately, this setup seems to draw more power than just HDMI and the mouse stopped working. It was a gift and does have a few embellishments, not least that it looks like a toy car! The logitech keyboard is fine and the LEDs in the mouse ignite, it just doesn't work. I was in Poundland

Perhaps that goes some way to answer the perennial question "which mouse should I use with a Pi?"

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from Tim Hill who welcomes incoming email to tim at timil dot com. 
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Reply to
Tim Hill
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Get a powered hub, you run the mouse of the hub along with any other USB peripherals. It can power the Pi itself so you still only need one plug. Look on the Pi website for recommended ones.

---druck

Reply to
druck

Why not get a higher current PSU for the rPi? All my mice are wireless these days.

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Rick
Reply to
rickman

You just need to be careful about the total current going THROUGH the pi. It's safer to power as much as you can via an external USB hub, with the bonus that it can usually power the pi as well.

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Alan Adams, from Northamptonshire 
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http://www.nckc.org.uk/
Reply to
Alan Adams

The issue with the model B is that the input power is limited/protected via a 700mA self-resetting fuse (polyfuse) So while on the later B's (rev

1.1 and 2) the USB sockets themselves are not protected the overall limit relains. Thats why a powered hub is recommended for B's with power-hungry USB peripherals.

(And power-hungry HDMI -> VGA devices too - they're powered off the Pi's

5v line and have lots of active widgetry inside them)

The B+ has a much better power design and the input polyfuse is 2amps and the USB ports are fed via an electronic current limiter that is settable in software to allow 600mA or 1.2A through all 4 USB sockets.

You still need a good PSU to feed it though!

Gordon

Reply to
Gordon Henderson

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for a way of powering the adapter itself, so it draws less from the Pi

Reply to
ajw99uk

Nice hack I fond performance of my HDMI adaptor to be very flaky & gave up, I may take another look now

--
In America, it's not how much an item costs, it's how much you save.
Reply to
alister

In a mad moment - alister mumbled :

If you modify these adaptors to be powered directly from a POWERED USB HUB, disconnecting the power from the HDMI input, you will find they work very well.

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|)ryn [vans            mail to - BrynEvans@bryork.freeuk.com
Reply to
Bryn Evans

mine looks like there is sufficient room in the case to as a switched DC jack that should give me the best of both worlds :-)

--
Kiss me twice.  I'm schizophrenic.
Reply to
alister

In a mad moment - alister mumbled :

Why complicate things ?

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|)ryn [vans            mail to - BrynEvans@bryork.freeuk.com
Reply to
Bryn Evans

soldering in a power SKt is no more complicated that attaching a USB cable. in the long term it provides better flexibility (i have another device I use this adapter with that does not require any external power)

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HOW YOU CAN TELL THAT IT'S GOING TO BE A ROTTEN DAY: 
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Reply to
alister

Thanks, I bear that in mind.

--
from Tim Hill who welcomes incoming email to tim at timil dot com. 
* Share in a better energy supplier: http://tjrh.eu/coopnrg 
* Share in cheaper ethical telecoms: http://tjrh.eu/phone 
* Have a genuine & spam-proof address for Usenet http://www.invalid.org.uk/
Reply to
Tim Hill

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