Milliways
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Model B+ documentation

Wed Nov 26, 2014 12:39 am

The Raspberry Pi Model B seems to be well documented. There are lots of guides and trouble shooting hints.

The Model B+ does NOT seems to be well documented. (This is made even harder due to the unfortunate name, as you can't search for '+').

I can't find any description of the LEDs on the newer boards. I am intrigued by the actual voltage at which the Red LED fails to light.

It is not difficult for an Electrical Engineer to examine the B schematics and the Raspberry Pi B+ (Reduced Schematics) to work out what is going on, but the target Beginner and Educational users need more explicit data.

Is there an accessible guide to the B+ connections, LEDs etc that I have missed?

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rpdom
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Re: Model B+ documentation

Wed Nov 26, 2014 6:59 am

For the most part, troubleshooting on the B+ should be the same as the B.

The main differences are the LEDs, as you have said.
The Power LED goes out at around 4.65V. This is accompanied by a small coloured square appearing on the top right of the screen.
The ACT LED lights up and doesn't go out if the Pi can't read the microSD card (On the A/B it would glow very faintly instead).

DirkS
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Re: Model B+ documentation

Wed Nov 26, 2014 10:08 am

(This is made even harder due to the unfortunate name, as you can't search for '+')
I actually find that Google is pretty good at finding B'+' specific articles, etc.
If you're talking about the forum search: use google and add 'site:www.raspberrypi.org' to your search terms.

Gr.
Dirk.

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mahjongg
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Re: Model B+ documentation

Wed Nov 26, 2014 11:57 am

The schematics with most differences between a B and B+ is available at the usual place (where all other schematics can be found also), missing from it are the USB current limiters, but most else is available, including how the PWR and ACT LEDs are connected. The Ethernet LED's are (mostly) still there but moved to the ethernet jack.

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joan
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Re: Model B+ documentation

Wed Nov 26, 2014 12:08 pm

mahjongg wrote:The schematics with most differences between a B and B+ is available at the usual place (where all other schematics can be found also), missing from it are the USB current limiters, but most else is available, including how the PWR and ACT LEDs are connected. The Ethernet LED's are (mostly) still there but moved to the ethernet jack.
I haven't seen a definitive statement about the meaning of the Ethernet socket LEDs. Does anyone know for sure what they indicate?

ShiftPlusOne
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Re: Model B+ documentation

Wed Nov 26, 2014 12:22 pm

joan wrote:
mahjongg wrote:The schematics with most differences between a B and B+ is available at the usual place (where all other schematics can be found also), missing from it are the USB current limiters, but most else is available, including how the PWR and ACT LEDs are connected. The Ethernet LED's are (mostly) still there but moved to the ethernet jack.
I haven't seen a definitive statement about the meaning of the Ethernet socket LEDs. Does anyone know for sure what they indicate?
Yellow:
This pin is driven low (LED on) when the Ethernet
operating speed is 100Mbs, or during auto-
negotiation. This pin is driven high during 10Mbs
operation, or during line isolation
Green:
This pin is driven low (LED on) when a valid link is
detected. This pin is pulsed high (LED off) for
80mS whenever transmit
or receive activity is
detected. This pin is then driven low again for a
minimum of 80mS, after which time it will repeat
the process if TX or RX activity is detected.
Effectively, LED2 is activated solid for a link. When
transmit or receive activity is sensed, LED2 will
function as an activity indicator
http://ww1.microchip.com/downloads/en/D ... c/9514.pdf

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joan
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Location: UK

Re: Model B+ documentation

Wed Nov 26, 2014 12:26 pm

Thanks.

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