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Re: The Raspberry Pi 2 Q&A thread

Posted: Wed Feb 04, 2015 4:45 pm
by guzunty
jdb wrote:
guzunty wrote:
RaTTuS wrote:thread locking via different CPU cores ?
Can you run the same test on a Pi1 that is fully up to date?
Done. Fully updated B+ shows expected 1ms delay.

I can supply LA images if you need them.

Re: The Raspberry Pi 2 Q&A thread

Posted: Wed Feb 04, 2015 5:00 pm
by BMS Doug
pi-man-uk wrote:Hi, just a question on the upgrade process, I’m planning to transition my main server from a model b to my new pi2 tonight. I’ve just apt-get updated/upgraded and noticed /boot got full up of new kernels etc on the pi1, rebooted it and it came back - so I figure I’m good to go. Sooooo, next step, I plan tonight to shut it down, stick the 4 gig full size SD card in my macbook and use dd to create an image file from it on the mac, then I plan to use dd again to write that image file to a 4 gig class 10 *micro SD* card – stick this in the new pi2, boto and it’s off to the races. Will it work?


Have you run a dist-upgrade or just upgrade? I think you need to dist-upgrade but I'd suggest copying the card first.

With dist-upgrade it should work, I'd try the new card in an adaptor in the pi1 first.

Re: The Raspberry Pi 2 Q&A thread

Posted: Wed Feb 04, 2015 5:12 pm
by ShiftPlusOne
jamesh wrote: Did we mention it was faster?
Other way around. Right now, when DT is enabled, the delay only counts in jiffies (100 Hz). It catches an extra tick, so the minimum delay ends up being 20ms (*1000=20s).

Re: The Raspberry Pi 2 Q&A thread

Posted: Wed Feb 04, 2015 5:37 pm
by pi-man-uk
BMS Doug wrote:
pi-man-uk wrote:Hi, just a question on the upgrade process, I’m planning to transition my main server from a model b to my new pi2 tonight. I’ve just apt-get updated/upgraded and noticed /boot got full up of new kernels etc on the pi1, rebooted it and it came back - so I figure I’m good to go. Sooooo, next step, I plan tonight to shut it down, stick the 4 gig full size SD card in my macbook and use dd to create an image file from it on the mac, then I plan to use dd again to write that image file to a 4 gig class 10 *micro SD* card – stick this in the new pi2, boto and it’s off to the races. Will it work?

Have you run a dist-upgrade or just upgrade? I think you need to dist-upgrade but I'd suggest copying the card first.

With dist-upgrade it should work, I'd try the new card in an adaptor in the pi1 first.
I just went for upgrade - always been a bit curious as to the difference, I'll run a dist-upgrade also for good measure - I've also taken a backup of /home/pi .... thanks for tips.

Re: The Raspberry Pi 2 Q&A thread

Posted: Wed Feb 04, 2015 5:42 pm
by juppiter89
Did anyone already try to overclock Rpi2? I would like to know if it's possible to bring it fairly easily to 1200 mhz.
Thanks :)

Re: The Raspberry Pi 2 Q&A thread

Posted: Wed Feb 04, 2015 6:13 pm
by dom
juppiter89 wrote:Did anyone already try to overclock Rpi2? I would like to know if it's possible to bring it fairly easily to 1200 mhz.
It overclocks to a similar level as Pi1.
I'd say most (but not all) Pi2's can run at 1000MHz, a minorty at 1100Mhz, and 1200MHz is possible but rare.

Re: The Raspberry Pi 2 Q&A thread

Posted: Wed Feb 04, 2015 6:16 pm
by joan
In the earlier Pi models the peripherals were at bus address 0x7E000000 and ARM physical memory address X was at bus address 0x40000000 + X.

Are the peripherals still at bus address 0x7E000000?

Re: The Raspberry Pi 2 Q&A thread

Posted: Wed Feb 04, 2015 6:17 pm
by Trixster
Mine's running at 1000MHz, core and sdram at 500MHz, overvolt at 2, no problems whatsoever. That'll do nicely!

Re: The Raspberry Pi 2 Q&A thread

Posted: Wed Feb 04, 2015 6:43 pm
by ThePolo
Now that pi 2 offer 1.2A over USB, is it possible to connect a 2.5inch USB hard disk without external power? Thanks :D

Re: The Raspberry Pi 2 Q&A thread

Posted: Wed Feb 04, 2015 6:46 pm
by dom
joan wrote:In the earlier Pi models the peripherals were at bus address 0x7E000000 and ARM physical memory address X was at bus address 0x40000000 + X.

Are the peripherals still at bus address 0x7E000000?
Bus addresses are unchanged (they are in the GPU world which is unchanged), so peripherals are at 0x7e000000. L2 cached sdram is at 0x40000000 and uncached sdram is at 0xc0000000 as before.

The arm side physical to bus mapping has changed.
Pi1 maps 0 to 0x40000000 (as GPU L2 cache is used for normal memory accesses).
Pi2 maps 0 to 0xc0000000 (as GPU L2 cache is not used for normal memory accesses).

Pi1 maps 0x20000000 to 0x7E000000 (for peripherals).
Pi2 maps 0x3f000000 to 0x7E000000 (needed bumping to allow > 512M of RAM).

Re: The Raspberry Pi 2 Q&A thread

Posted: Wed Feb 04, 2015 6:52 pm
by gkreidl
ThePolo wrote:Now that pi 2 offer 1.2A over USB, is it possible to connect a 2.5inch USB hard disk without external power? Thanks :D
Yes, same as B+. You need a good 2A power supply.

Re: The Raspberry Pi 2 Q&A thread

Posted: Wed Feb 04, 2015 7:44 pm
by Paul Webster
The 3rd Pi1 in Dom's post above should be Pi2.

Done

Re: The Raspberry Pi 2 Q&A thread

Posted: Wed Feb 04, 2015 7:51 pm
by lingon
tvjon wrote: [email protected] ~ $ sudo hdparm -Tt /dev/mmcblk0p2

/dev/mmcblk0p2:
Timing cached reads: 974 MB in 2.00 seconds = 486.81 MB/sec
Timing buffered disk reads: 56 MB in 3.09 seconds = 18.11 MB/sec
[email protected] ~ $

[email protected] ~ $ sudo hdparm -Tt /dev/sda2

/dev/sda2:
Timing cached reads: 960 MB in 2.00 seconds = 480.20 MB/sec
Timing buffered disk reads: 86 MB in 3.01 seconds = 28.61 MB/sec
[email protected] ~ $
Thanks! Was this done with or without over clocking?

Re: The Raspberry Pi 2 Q&A thread

Posted: Wed Feb 04, 2015 8:46 pm
by Redfez
I can't get mine to boot beyond the dreaded rainbow screen of death. :?

Tried updating the card beforehand on my other Pi in preparation. Good quality 2A power supply from reputable dealer. Micro SD card is branded one that works fine in other Pis...stumped as to what is going wrong. Is there a step in preparation I've missed?

Re: The Raspberry Pi 2 Q&A thread

Posted: Wed Feb 04, 2015 8:58 pm
by DirkS
Redfez wrote:I can't get mine to boot beyond the dreaded rainbow screen of death. :?

Tried updating the card beforehand on my other Pi in preparation. Good quality 2A power supply from reputable dealer. Micro SD card is branded one that works fine in other Pis...stumped as to what is going wrong. Is there a step in preparation I've missed?
If you have a spare SD card download the latest Raspbian and see if that works with your hardware.
If it does it's time to troubleshoot your old SD card

BTW: did you run 'upgrade' or 'dist-upgrade'?

Re: The Raspberry Pi 2 Q&A thread

Posted: Wed Feb 04, 2015 9:03 pm
by paulie
jdb wrote: To use an existing card on Pi2 you need
- Recent firmware
- kernel7.img
- ARMv7 kernel modules.

To upgrade an SD card for Pi 2 use:
sudo apt-get update && sudo apt-get upgrade
I have one or two Pi2 on order. If I do the update/upgrade, will I still be able to use the microsd card in my model B v1 ?
Or is it a one-way process? ( still have to source a 300mm 40 to 26-way gpio cable, to use TNC-Pi inside HDMIPi this weekend * so may have to revert)

* thanks to those who suggested where...

Re: The Raspberry Pi 2 Q&A thread

Posted: Wed Feb 04, 2015 9:05 pm
by Mequa
dom wrote:
juppiter89 wrote:Did anyone already try to overclock Rpi2? I would like to know if it's possible to bring it fairly easily to 1200 mhz.
It overclocks to a similar level as Pi1.
I'd say most (but not all) Pi2's can run at 1000MHz, a minorty at 1100Mhz, and 1200MHz is possible but rare.
I've had no problem with overclock to 1000MHz using a 1.2A power supply, even with USB wireless keyboard and mouse. I'll probably need a more powerful supply if I add Wi-Fi.

Trying this overclock with a puny 1A power supply (most likely inadequate for the Pi 2 Model B, so I'll keep that for charging my Kindle) leads to freeze-ups in Raspbian, and a small rainbow-coloured square in the top-right of the screen, which I suspect is an inadequate power notification.

Re: The Raspberry Pi 2 Q&A thread

Posted: Wed Feb 04, 2015 9:06 pm
by Redfez
DirkS wrote:
Redfez wrote:I can't get mine to boot beyond the dreaded rainbow screen of death. :?

Tried updating the card beforehand on my other Pi in preparation. Good quality 2A power supply from reputable dealer. Micro SD card is branded one that works fine in other Pis...stumped as to what is going wrong. Is there a step in preparation I've missed?
If you have a spare SD card download the latest Raspbian and see if that works with your hardware.
If it does it's time to troubleshoot your old SD card

BTW: did you run 'upgrade' or 'dist-upgrade'?
I tried upgrade first, when that didn't work I tried it with dist-upgrade and got the same results. The SD card still works fine in a B+ though so it doesn't seem to be the card. I've tried 2 SD cards in the Pi2 so far using the previously mentioned approach. I'm downloading the latest one now from this site to put on another card and I'll see if that makes any difference.

Re: The Raspberry Pi 2 Q&A thread

Posted: Wed Feb 04, 2015 9:33 pm
by jdb
This is a Q&A thread, not individual support. Start a new thread in Troubleshooting.

Re: The Raspberry Pi 2 Q&A thread

Posted: Wed Feb 04, 2015 9:34 pm
by jdb
paulie wrote:
jdb wrote: To use an existing card on Pi2 you need
- Recent firmware
- kernel7.img
- ARMv7 kernel modules.

To upgrade an SD card for Pi 2 use:
sudo apt-get update && sudo apt-get upgrade
I have one or two Pi2 on order. If I do the update/upgrade, will I still be able to use the microsd card in my model B v1 ?
Or is it a one-way process? ( still have to source a 300mm 40 to 26-way gpio cable, to use TNC-Pi inside HDMIPi this weekend * so may have to revert)

* thanks to those who suggested where...
Updated/upgraded SD cards retain compatibility with Pi 1 models.

Re: The Raspberry Pi 2 Q&A thread

Posted: Wed Feb 04, 2015 10:56 pm
by dom
Paul Webster wrote:The 3rd Pi1 in Dom's post above should be Pi2.
Corrected.

Re: The Raspberry Pi 2 Q&A thread

Posted: Wed Feb 04, 2015 11:38 pm
by Greg Erskine
Hi all,

Just fired up my Pi2 and checked the Revision number.

Got: a21041, I was expecting 0013.

Is this the official revision number or an error?

EDIT: Just found this information http://wiringpi.com/wiringpi-updated-for-the-new-pi-v2/

regards
Greg

Re: The Raspberry Pi 2 Q&A thread

Posted: Thu Feb 05, 2015 12:14 am
by AndyD
Greg Erskine wrote:Hi all,

Just fired up my Pi2 and checked the Revision number.

Got: a21041, I was expecting 0013.

Is this the official revision number or an error?

EDIT: Just found this information http://wiringpi.com/wiringpi-updated-for-the-new-pi-v2/

regards
Greg
On that page Gordon says "the foundation has actually encoded a lot more information into the Revision field". Does anybody know what information is encoded in the Revision field of /proc/cpuinfo on the Pi2?

Re: The Raspberry Pi 2 Q&A thread

Posted: Thu Feb 05, 2015 12:16 am
by macbreak
Greg Erskine wrote:Hi all,

Just fired up my Pi2 and checked the Revision number.

Got: a21041, I was expecting 0013.

Is this the official revision number or an error?

EDIT: Just found this information http://wiringpi.com/wiringpi-updated-for-the-new-pi-v2/

regards
Greg

Shhhh! You've accidentally been sent a Pi 3 prototype with Intel Atom Z3735G CPU and 4GB DDR3... :lol:

Re: The Raspberry Pi 2 Q&A thread

Posted: Thu Feb 05, 2015 2:23 am
by PuppetHoundZ
What's the Performance comparisions of a Raspberry Pi 1 B+ in turbo mode vs a Raspberry Pi 2 B on default clock? That would be a interesting piece of info! :geek: