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by clivem
Sat Jul 16, 2016 9:08 pm
Forum: Advanced users
Topic: Add External Antenna to Raspberry Pi 3
Replies: 9
Views: 13766

Re: Add External Antenna to Raspberry Pi 3

A Mediatek mt7601u chipset dongle from ePay is one way of doing it. The included (in the default RPi kernel build mt7601u) driver works well, so you don't have to worry about building and using out-of-tree modules. MT7601U Receptor WIFI USB MT7601 chip mediatek mini antena para portatil Should be ab...
by clivem
Mon May 16, 2016 8:40 am
Forum: General discussion
Topic: A picture from The Pi Hut
Replies: 283
Views: 47502

Re: A picture from The Pi Hut

texy wrote:
Gavinmc42 wrote: No, the camera adapter cable is £4.
LOL. Yep, £4 for a Pi Zero board, complete with camera connector.... No price rise..... But you want the 20 cent cable to actually connect a camera to it and that will double the price to £8! Seriously, £4 for that 15cm "cable"....
by clivem
Fri May 13, 2016 8:28 am
Forum: General discussion
Topic: Audio clipping on digital output?
Replies: 7
Views: 2685

Re: Audio clipping on digital output?

LOL. I just read that thread. It appears that someone is connecting a 2V full scale output from their DAC, to a soundcard with a 1V full scale input and wondering why the "test results" (and I use that term very loosely because RMAA is the "testing" software) show distortion......
by clivem
Mon Mar 28, 2016 10:44 am
Forum: Advanced users
Topic: Analogue audio testing
Replies: 265
Views: 133966

Re: Analogue audio testing

When I get an opportunity I will try it with a value of 1 (just to see if it makes a difference). Ronnie, SL_ALSA_PARAMS="-a :::0" will leave the other params at defaults, but disable mmap. Likewise, SL_ALSA_PARAMS="-a :::1", will force mmap. If the first results in good audio replay and the second...
by clivem
Sun Mar 27, 2016 11:21 pm
Forum: Advanced users
Topic: Analogue audio testing
Replies: 265
Views: 133966

Re: Analogue audio testing

SL_ALSA_PARAMS="-a 80:4:24:0" The sound is now playing properly and there have been no break ups or interruptions (apart from when I have had to restart the player). I'm guessing, but probably the fourth arg, disabling mmap for data transfer that is "fixing" or hiding the issue..... ISTR, that sque...
by clivem
Sun Mar 27, 2016 10:47 pm
Forum: Advanced users
Topic: RPi3 BT power and reset pins
Replies: 6
Views: 1449

Re: RPi3 BT power and reset pins

This is a real shame. I had troubles with the AP6210 on the CubieTruck years ago and managed to fix them by changing the patchram program and also controlling the relevant GPIO pins. Perhaps one shouldn't have to do this but unfortunately one does sometimes. LOL. Yes, been there, seen that, done it...
by clivem
Sun Mar 27, 2016 10:23 pm
Forum: Advanced users
Topic: RPi3 BT power and reset pins
Replies: 6
Views: 1449

Re: RPi3 BT power and reset pins

Are there any schematics for the RPi3 ? Or any details about the 43430 ? Or any details of the GPIO pins that connect to the BT/WiFi chip ? Or any other details that may help me here ? LOL. Best of luck getting the info you seek..... You can't get the 43430 datasheet from Broadcom without NDA.... P...
by clivem
Fri Mar 18, 2016 9:34 pm
Forum: General discussion
Topic: Pi3 incorrect results under load (possibly heat related)
Replies: 105
Views: 53319

Re: Pi3 incorrect results under load (possibly heat related)

What exactly are you getting at here? I hope you don't think I am ignoring you. I can't really answer that question without posting what I have found, which I don't want to do before I have all my ducks in a row. Suffice to say, that I am now more intimately familiar with Linpack, openblas, vfpv3, ...
by clivem
Fri Mar 18, 2016 9:25 pm
Forum: General discussion
Topic: Pi 3 Overheating Issue?
Replies: 110
Views: 107486

Re: Pi 3 Overheating Issue?

Nickcn wrote:

Code: Select all

#Max out all CPU cores. Heats it up, loads the power-supply. 
for ((i=0; i<$(nproc --all); i++)); do nice yes >/dev/null & done
[/quote]

There are many ways of maxing..... Some are more max than others! ;)
by clivem
Fri Mar 18, 2016 1:08 am
Forum: General discussion
Topic: Pi 3 Overheating Issue?
Replies: 110
Views: 107486

Re: Pi 3 Overheating Issue?

I bought two Raspberry Pi 3s. One can't do anything complex, such as playing a youtube video, for long before it goes funny, mostly the running program just closes on it's own. Try appending "over_voltage=2" to the /boot/config.txt on the unstable one. There have been a couple of reports now that a...
by clivem
Thu Mar 17, 2016 3:02 pm
Forum: General discussion
Topic: Pi3 incorrect results under load (possibly heat related)
Replies: 105
Views: 53319

Re: Pi3 incorrect results under load (possibly heat related)

It's definitely not out-of-memory. The benchmark finishes, it's just the correctness (residual) checks fail. Would you mind humouring me, and recompile your OpenBLAS library and test again? Build OpenBLAS with "make TARGET=ARMV6 DYNAMIC_ARCH=0 USE_THREAD=1 USE_OPENMP=0". From multiple runs, do you ...
by clivem
Tue Mar 15, 2016 10:43 pm
Forum: General discussion
Topic: Pi3 incorrect results under load (possibly heat related)
Replies: 105
Views: 53319

Re: Pi3 incorrect results under load (possibly heat related)

Failure at stock frequencies on running a real-world application is a big deal. I am glad you said that. If the numbers generated from my NEON FFT functions on Pi3B, which differ from the numbers being generated by 4 other ARMv7 boards, and the same code running on Pi2B are any indication, it looks...
by clivem
Tue Mar 15, 2016 9:13 pm
Forum: General discussion
Topic: Pi3 incorrect results under load (possibly heat related)
Replies: 105
Views: 53319

Re: Pi3 incorrect results under load (possibly heat related)

Curious.... I just checked that my +2'd board is still running cpuburn-a53 and hasn't locked. Same, with the board that requires +4. It's still crunching..... Tomorrow I'll actually run a few files through my NEON transcode and bit compare the results with a file created on another SBC, that is know...
by clivem
Tue Mar 15, 2016 9:08 pm
Forum: General discussion
Topic: AArch64 code execution on Raspberry Pi3.
Replies: 36
Views: 19026

Re: AArch64 code execution on Raspberry Pi3.

I finally got my hands on a Raspberry Pi3 and tested it against a DragonBoard410c running 64-bit Linux. ..... For my optimized NEON code (intrinsics for portability), running in 64-bit mode gained 0-25% depending on the complexity of the code. Yep, I did some very similar testing with Dragonboard v...
by clivem
Tue Mar 15, 2016 7:35 pm
Forum: General discussion
Topic: Pi3 incorrect results under load (possibly heat related)
Replies: 105
Views: 53319

Re: Pi3 incorrect results under load (possibly heat related)

Sometimes one has to wonder if it wouldn't have been wiser to have made an effort to get boards into testers hands before the public launch and listen to any feedback that may have resulted........ Instead of the secret squirrel, top secret bullshit, prior to launching the new hardware....... Instea...
by clivem
Tue Mar 15, 2016 7:09 pm
Forum: General discussion
Topic: Pi3 incorrect results under load (possibly heat related)
Replies: 105
Views: 53319

Re: Pi3 incorrect results under load (possibly heat related)

dom wrote: (2 works on my board).
Dom, I was going to leave this overnight....... +4, now appears to have stabilised the board that hard-locked as soon as it got the faint whiff of NEON code, and +2 on the ">100degC" board, seems to have it stable again.
by clivem
Tue Mar 15, 2016 12:34 am
Forum: General discussion
Topic: Pi3 incorrect results under load (possibly heat related)
Replies: 105
Views: 53319

Re: Pi3 incorrect results under load (possibly heat related)

I'm not convinced its anything to do with the supply voltage. I was being sarcastic. ;) There's nowt wrong with the 4x 2.5A supplies I purchased. It's down to silicon variations between individual Pi3B's, IMHO. I've already seen 10-15degC differences between units..... Same load, same voltages, sam...
by clivem
Mon Mar 14, 2016 10:48 pm
Forum: General discussion
Topic: Pi3 incorrect results under load (possibly heat related)
Replies: 105
Views: 53319

Re: Pi3 incorrect results under load (possibly heat related)

ejolson wrote: The fact that the system crashes before the CPU has a chance to overheat may implicate a faulty power supply or a too high resistance in the USB cable delivering the power.
Looks like I need to return 4x of the new "official" 2.5A power supplies to RS as well then......
by clivem
Mon Mar 14, 2016 10:31 pm
Forum: General discussion
Topic: pi 3 wifi range
Replies: 33
Views: 62479

Re: pi 3 wifi range

I think you meant IMO, not IMHO. No, definitely humbly suggesting that people upgrading from previous hardware, where they were using a USB wifi dongle, consider moving it to the Pi3B. If I wasn't being humble, I'd have been recounting my experiences with other SBC's that made the mistake of using ...
by clivem
Sun Mar 13, 2016 1:10 pm
Forum: General discussion
Topic: Pi3 incorrect results under load (possibly heat related)
Replies: 105
Views: 53319

Re: Pi3 incorrect results under load (possibly heat related)

This is a big issue, obviously. If throttling doesn't work correctly and/or there is a general stability issue, that is a major hardware fault of the Pi 3! Maybe the foundation should investigate this? As a first step I'm going to try to RMA the problematic Pi. I've now "thrown" 2x of the 8x Pi3B's...
by clivem
Sat Mar 12, 2016 7:02 pm
Forum: General discussion
Topic: pi 3 wifi range
Replies: 33
Views: 62479

Re: pi 3 wifi range

Like most things, especially in the Pi universe, you really do get what you pay for, and that's certainly the case with the Pi3B wifi.... For a start, on paper you are limited to single channel (20MHz) width 'n', so 72Mbps. In reality, with it connected to a dedicated AP, only a few metres distance ...
by clivem
Tue Mar 08, 2016 11:58 pm
Forum: Advanced users
Topic: Documentation bugs: RPi2&3 GPIO electrical specs
Replies: 133
Views: 16854

Re: Documentation bugs: RPi2&3 GPIO electrical specs

> belt and braces Why are you guys focusing only on the pull-ups? Pull-ups are important! Belt's and braces..... Some of us prefer not to be wandering around with our pants round our ankles, whether we have a spec sheet in our hands or not! ;) Anyway, seriously, I hope James manages to get released...
by clivem
Tue Mar 08, 2016 11:39 pm
Forum: Advanced users
Topic: Documentation bugs: RPi2&3 GPIO electrical specs
Replies: 133
Views: 16854

Re: Documentation bugs: RPi2&3 GPIO electrical specs

The fact that you can do other things with it is a bonus but should never be taken for granted any more than you would take it for granted with any other 3.3V logic device. I think the belt and braces EE types, would make the point that by having a full set of specifications, they don't need to gue...
by clivem
Tue Mar 08, 2016 11:34 pm
Forum: Advanced users
Topic: Documentation bugs: RPi2&3 GPIO electrical specs
Replies: 133
Views: 16854

Re: Documentation bugs: RPi2&3 GPIO electrical specs

On a meta note, I don't entirely understand why a few posters on here argue so strongly against publication of these specs, and our asking for them. If you don't want them for your applications, great, don't use them. But calling the rest of us incompetent for practicing engineering using calculati...

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