Raspberry Pi Forums

Hello all,

is there such a thing as a bad keyboard?

The reason i ask this is because i have had video issue's with my PI 2, which i have now returned as faulty, (I don't know if it was faulty, but a CPC tech guy thought it was, and i didn't know what the heck else to do and the time was almost up!)

I have since been reading about power and the usb power use, i am total PI 2 noob btw, but the keyboard just came to my mind, because i wasn't using any other usb device's, the only thing i wanted my pi to do was read files off my NAS, which it couldn't do without flickering and flashing see old thread http://www.raspberrypi.org/forums/viewt ... 101934&e=0

I came to this conclusion, (which could be wrong), that as i have the official PSU for the PI 2 from CPC, so it cant be that, and i have no other usb devices plugged in.

I'm unable to use a remote for the PI 2 via a phone as i don't have an iphone or an android phone.
Hence me using a keyboard, Microsoft Wireless Multimedia thingy, i will update this thread tomorrow with the model.

Does anyone out there use this keyboard with their PI 2?

Are you using it without issue?

How do i find out how much power it is using or is required by it?

Is it a possibility it is using too much power from the usb port on the PI 2?

Please note that the keyboard works perfectly.


Regards


Dexter24

Dexter24FTW wrote:Hello all,

is there such a thing as a bad keyboard?

There certainly can be, for a variety of types of "bad". That can be anywhere from non-functional to poor typing "touch" (a *very* common problem with keyboards). It is also possible for a keyboard to require more power than a Pi can deliver (much less likely these days than with the early model Pis).

How do i find out how much power it is using or is required by it?

Is it a possibility it is using too much power from the usb port on the PI 2?

Please note that the keyboard works perfectly.

It *should* be marked for power requirements. Unfortunately, a great many keyboards are not marked, and if they are, they just show the max allowed for USB 2.0: 500mA, which is unlikely to reflect the actual requirements. You can check on line to see if you can find the technical specs for the keyboard, but since the general assumption will be that the keyboard will be used with a PC, the actual power requirements aren't important so long as they don't exceed the USB 2.0 spec.

In general terms, the simpler keyboards (no fancy lighting, no elaborate "bells & whistles") will require less current than the fancy ones.

Note also that the total current (it's all 5v) available to the USB ports (collectively) is 600mA. There is a config.txt option that can boost that to 1200mA.

One thing you might try is to buy or borrow another keyboard and try that. If the alternate keyboard works with the Pi, then be suspicious of the one that doesn't. A decent, inexpensive keyboard is the Logitech K120. I've used them extensively with Pis (including very early Pis with 140mA polyfuses at the USB ports) with no problems.

Now having said all that, I see that you appear to be using a wireless keyboard. In that situation, the power requirements of the wireless dongle are what matter, and not the keyboard (though the principles are the same). My one wireless keyboard and mouse set (HP) has a dongle that is marked to draw 30mA...a current level that won't bother any Pi ever made. But be aware that wireless keyboards require batteries...so check that the batteries in the keyboard are in good shape.

Hi,


Thank you for your very detailed and helpful post, good idea on changing the batteries, they have been in a while and it hasn't been used, and your suggestion of the receiver, i had not thought of that.

The model is Microsoft Wireless Laser Keyboard 6000 V2.0

The receiver says on it, wireless optical desktop receiver 3.0A
--- 5V 100mA

I have changed the batteries now for fresh, but as i am awaiting for a replacement pi 2, another 2 weeks, i will not know till then if i have the same problem or not.

I would rather not buy another keyboard, as i bought the PI 2 for its cheapness and because my "Popcorn A 100" died, and i have limited funds, i was working when i bought the A100, i am not atm.

I would also have to sit very close to the TV/PI to control it, which would be very annoying.


Thanks


Dexter24

Go into your local supermarket that sells computer tat, wherever that may be, buy the cheapest keyboard they offer, it'll work......

pluggy wrote:Go into your local supermarket that sells computer tat, wherever that may be, buy the cheapest keyboard they offer, it'll work......

I found one in Basingstoke's B&M (http://www.bmstores.co.uk/products/trus ... ard-272697) for £5.99 last week. Haven't bought one to test, but it looked cheap enough.

IF the cost of a $10 to $15 keyboard is a financial strain (you have my sympathy...been there), see if you can borrow a keyboard from a friend or relative long enough to test with it once you get your replacement Pi. One advantage of the Pi is that you can take all the needed equipment (Pi, power, mouse, cables) to another location to test with another keyboard.

As for the markings on the dongle...I wonder if the "3.0A" just USB 3.0, type A connector. The Pi has USB 2.0 ports.