The Raspberry Pi Model B+ Q&A thread

[fruitoftheloom]

Thank you RS received the B+ and a 2A PSU this afternoon.

Overclocked to high, have cheap USB Mouse and Keyboard as well as a generic RTL8188CUS WiFi Adaptor installed.

Started with a NEW Raspbian Wheezy Image and it is very stable, no WiFi dropouts, no reboots. All good

Did you set the USB high power option?

Shouldn't need to with those devices.

OK, thanks for advice. Have now set up Bluetooth pairing with my Phone and File Transfer is AOK. Cool Beans

Bus 001 Device 002: ID 0424:9514 Standard Microsystems Corp.
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 003: ID 0424:ec00 Standard Microsystems Corp.
Bus 001 Device 004: ID 1c4f:0032 SiGma Micro
Bus 001 Device 005: ID 1c4f:0002 SiGma Micro Keyboard TRACER Gamma Ivory
Bus 001 Device 007: ID 0bda:8176 Realtek Semiconductor Corp. RTL8188CUS 802.11n WLAN Adapter
Bus 001 Device 006: ID 0a12:0001 Cambridge Silicon Radio, Ltd Bluetooth Dongle (HCI mode)

[AndrewS]

With the switch mode PSU on board it will boot to login prompt on as little as 2.6V into the micro USB.
USB peripherals on the Pi ports are unlikely to work, and I don't know what works on the Pi itself, but it will boot and drive HDMI.

I guess that probably depends on the particular HDMI device you're connected to?

[PiGraham]

With the switch mode PSU on board it will boot to login prompt on as little as 2.6V into the micro USB.
USB peripherals on the Pi ports are unlikely to work, and I don't know what works on the Pi itself, but it will boot and drive HDMI.

I guess that probably depends on the particular HDMI device you're connected to?

The obvious things that might not work at such low voltages are anything powered by 5V, such as USB peripherals, or HDMI converters. Intriguingly I am using an HDMi-VGA converter and it still works right down to 2.6V in.
I suspect that a direct HDMI connection will be OK.

I'm tempted to run the B+ direct from a single LiPo (~3V to 4.2V).

NB Using a Pi B+ at such low voltages is not recommended! If you try it proceed at your own risk. The system may be unstable. You could corrupt your SD card.

[redhawk]

Does anyone have a photo of the B+ board underside in a decent resolution (to see labels and components clearly)??

Also since power routing has been revamped are these HDMI converters that use the HDMI 5v supply line for power safer now or does the RPF still recommended ones with external power supply??

Richard S.

[AndrewS]

Does anyone have a photo of the B+ board underside in a decent resolution (to see labels and components clearly)??

http://www.raspberrypi.org/introducing- ... ent-957694

[tvoverbeek]

Does anyone have a photo of the B+ board underside in a decent resolution (to see labels and components clearly)??

On the Adafruit product page for the B+ there is a photo on the underside.
Better resolution on their flickr photostream: https://www.flickr.com/photos/adafruit/ ... otostream/

[alexeames]

Does anyone have a photo of the B+ board underside in a decent resolution (to see labels and components clearly)??

The forum will shrink the embed, so the URL is here...

http://raspi.tv/wp-content/uploads/2014 ... d_1500.jpg

[usul27]

Hows the i2c eeprom for board function going to be used, will there be config files for the bootloader etc?
This is already under discussion here http://www.raspberrypi.org/forums/viewt ... 44&t=81733

Not much point discussing it as the specifications and software support hasn't been written yet. But they are GPIO0 and GPIO1, I2C0.[/quote]

Can I just use my own code to use this? As I plan to upgrade a board to the new RPi B+, I would need a specification soon. My idea would be just to use a normal EEPROM and write a string into it "board xyz". The driver would then read the content of the EEPROM and check for this string. Would this be ok?

[mahjongg]

The status leds are more modest. Just two instead of four. On the old board these light were very bright.

The ethernet status LED's are now on the Ethernet port (where they belong), there is only place for two LED's not the original three, and for the moment its not clear which two functions were chosen from the original three (full-duplex, connected, and 10/100mbps). i'm guessing the least useful one (full-duplex?!) was dropped, but it might be possible to change the function of each LED, as each LED output can also be completely software driven when programmed as "GPIO".

[AndrewS]

it might be possible to change the function of each LED, as each LED output can also be completely software driven when programmed as "GPIO".

But bear in mind that this is "GPIO" connected to the LAN9514 chip, and not the 'traditional GPIO' connected to the BCM2835

[mahjongg]

The forum will shrink the embed, so the URL is here...

http://raspi.tv/wp-content/uploads/2014 ... d_1500.jpg

two solutions to that:

• Open the picture in a new windows (or tab) and it will be displayed full size, but the forum reader must be aware of that
  
  or
• Use the "Normal" pulldown option to enlarge the picture, for example here is the same picture enlarged to "Huge"

[jaybee007]

Hi, all
I got my model b + from cpc today
Fitted a sd notro's master image. Powered it up, everything is fine apart from the Ethernet and USB ports are not working ???
Not sure what it could be maybe just a faulty board. I was wondering if anyone else had experienced this or solved this issue. Or is it going back to cpc lol
Thanks guys

[plugwash]

Hi, all
I got my model b + from cpc today
Fitted a sd notro's master image. Powered it up, everything is fine apart from the Ethernet and USB ports are not working ???
Not sure what it could be maybe just a faulty board. I was wondering if anyone else had experienced this or solved this issue. Or is it going back to cpc lol
Thanks guys

Most likely the SD card image you used hasn't been updated for the B+.

[AndrewS]

Fitted a sd notro's master image. Powered it up, everything is fine apart from the Ethernet and USB ports are not working ???

http://www.raspberrypi.org/forums/viewt ... 63#p579163

[DougieLawson]

Try running with a copy of the stock Raspbian. You need a firmware update to run on a B+.

You could boot the SDCard in your old RPi B and run rpi-update on that machine before swapping to the new B+.

[jaybee007]

Most likely the SD card image you used hasn't been updated.

Ohh ok thanks for that, I hadn't realised that the kernel would need updating. The image works the way it should, by that I mean the screen starts just no Ethernet or usb I will update the kernel and see how things are after that.
Thanks again

Edit : yeah a rpi-update resolves no usb problem
Thanx guys

[JRV]

According to the CPC website the GPIO pins have been extended from 26 to 40 it also claims that it's backwards compatible with existing 26 pin projects.
This is actually wrong since a 26 pin connector will not be able to sit on a 40 pin GPIO due to the housing hitting pins 27 and 28.

How can this be considered "backwards compatible" ??

Would it be possible to remove pins 27 and 28 without crippling the functionality of the GPIO??

It is not necessary to remove pins 27 and 28, This part will work as an adapter: http://www.adafruit.com/products/1112

[gordon77]

Try running with a copy of the stock Raspbian. You need a firmware update to run on a B+.

You could boot the SDCard in your old RPi B and run rpi-update on that machine before swapping to the new B+.

To run what on a B+?

I just used the latest raspbian (20/7) and it worked in my B and B+, and USB seemed to work OK with no other updates.

Gordon77

[DirkS]

I just used the latest raspbian (20/7)

20/6 ?

[gordon77]

I just used the latest raspbian (20/7)

20/6 ?

Sorry Yes. I haven't got one from the future!

[mahjongg]

it might be possible to change the function of each LED, as each LED output can also be completely software driven when programmed as "GPIO".

But bear in mind that this is "GPIO" connected to the LAN9514 chip, and not the 'traditional GPIO' connected to the BCM2835

Thats why I did put GPIO between quotes.

[arm2]

First of all, Congrats for getting out of beta The new revision looks awesome.

Question: Will unpowered HDMI>VGA converters be safer to use with the B+? I gather it was just a matter of 1 diode before...

Yes. The HDMI hotplug supply now has a current limit device on it, similar to the USB output current limit.

What is the current limited to?
Is that limit shared with anything else?

[mahjongg]

AFAIK is software controlled and can be either set to 600mA or double that (1200mA), I'm not aware that it's shared to anything else but the USB ports, but I did hear that the HDMI 5V output current is no longer limited to 50mA as it was before (by using a BAT54 diode) but now it also has a current controller device instead. Everything will be revealed with the release of the full sets of schematics, probably in a couple of weeks time.

[klricks]

Why does the red PWR LED flicker on and off in random pattern? RPi seems to be running fine. Have externally powered HDMI to VGA adapter. Cheap wired USB keyboard and mouse, 5V 10A industrial power supply. Green ACT LED flickers normally. (LED's not swapped as found by other poster).

Just noticed that the red LED will stay on solid if network cable is removed then flashes again with network plugged in.

[gordon@drogon.net]

Why does the red PWR LED flicker on and off in random pattern? RPi seems to be running fine. Have externally powered HDMI to VGA adapter. Cheap wired USB keyboard and mouse, 5V 10A industrial power supply. Green ACT LED flickers normally. (LED's not swapped as found by other poster).

Just noticed that the red LED will stay on solid if network cable is removed then flashes again with network plugged in.

The power LED is fed via a low-voltage detection circuit. If the voltage drops to below 4.63v then the power LED will go out.

It sounds like you have a marginal power supply - the new 3.3 & 1.8v regulator circuit is better able to cope with it (AIUI), but it still means that your power supply is marginal and you should consider a replacement. (Ethernet needs the 5v supply)

-Gordon