@Bikeman - What interesting things is your Pi Zero doing?
Currently it's just "burning-in" (E@H), It is supposed to replace the Raspi "1A" of my fish-eye "all-sky" meteor chasing camera (visible in the photo here https://www.raspberrypi.org/forums/download/file.php?id=11239 in the bowl next to the telescope). But for that I have to find the time to solder the IO connector pins to the Pi Zero (it drives a little LCD that idsplay some status information).
Meanwhile it's so hot here in northern Germany that I powered down almost all my crunchers...except for the Pis , of course :-)
as for the team, we have to make sure to celebrate when we brake thru 3.141592*10^6 !!
@Bikeman - What interesting things is your Pi Zero doing?
Currently it's just "burning-in" (E@H), It is supposed to replace the Raspi "1A" of my fish-eye "all-sky" meteor chasing camera (visible in the photo here https://www.raspberrypi.org/forums/download/file.php?id=11239 in the bowl next to the telescope). But for that I have to find the time to solder the IO connector pins to the Pi Zero (it drives a little LCD that idsplay some status information).
Meanwhile it's so hot here in northern Germany that I powered down almost all my crunchers...except for the Pis , of course :-)
as for the team, we have to make sure to celebrate when we brake thru 3.141592*10^6 !!
Cheers
HB
Once we break 3 million I'll try and watch the numbers daily and let everyone know when we are close.
I am down to 3 GPUs and 4 cores running at night, plus the RPi. I have fallen from 700K RAC to 200K+ and that is dropping. Depressing. :-(
With shaky hands and blurred vision me plus solder iron could only mean trouble. lol
I finally got time to spend assembling and filming the assembly of the cluster. My RAC will be dropping as my 1 Pi 3 was offline most of the weekend. I still have lots of the desktop configuration to shoot and I learned two things this morning that will make this even easier - 1) You can apparently now config WiFi from the /boot partition, meaning you don't have to get it online before connecting to WiFi and 2) Apparently the fixed OpenSSL so you no longer have to hold ca-certificates (which I just did a screen cast of last night).
So all of the "physical" filming is complete. I now just need to capture screencasts of the setup of the Pis, registration for E@H, and an overall introduction. I also need to record voice over narration for the physical assembly. It will be difficult because the only time it's quiet in my house is after the little ones are asleep! Optimistically, I'd like to be done with this within the week. I also have to be slow and methodical bringing up each node, carefully monitoring temperature because heat rises - hopefully the fans are up to the task!
Thank you to everyone who has supported the team and E@H on the Pi!
Noticed something last night on a Pi3 running Ubuntu 16. I was forced to relocate it and after booting I started to notice a small square in the upper right of the desktop appear/disappear. I googled and it stated that was due to a bad power supply or a bad cable. Interesting. In my move I had attached a 1 foot extension cable. I shut the Pi down a removed the 1 ft. cable. No more square. So if you see a small square maybe ....
Noticed something last night on a Pi3 running Ubuntu 16. I was forced to relocate it and after booting I started to notice a small square in the upper right of the desktop appear/disappear. I googled and it stated that was due to a bad power supply or a bad cable. Interesting. In my move I had attached a 1 foot extension cable. I shut the Pi down a removed the 1 ft. cable. No more square. So if you see a small square maybe ....
Specifically, the square is related to low voltage. Most USB Cables do not have large enough power carrying wires inside for large currents (standard USB 2 allowed for 500mW, or 100mA of current - the Pi 3 at full load draws ~4W, 800-1000mA). As current increases, voltage decreases because the wire acts is a resistor. To combat this you can do two things - use short cables or use cables with larger power wires inside. I chose to do both - http://www.amazon.com/Anker-4-Pack-PowerLine-Micro-USB/dp/B015XR60MQ?ie=UTF8&keywords=anker%20powerline%201ft&qid=1465300050&ref_=sr_1_3&sr=8-3
These cables are short and have much larger +5 and Ground wires inside. Most average USB cables were designed around 500mW power handling capabilities.
Additionally, it is also helpful to use a power supply that outputs up to 5.25V, which is still within USB spec. The higher voltage can also combat voltages losses due to small gauge wire or long runs.
I threw away several that measure badly and the no names are in a box for emergency charging jobs.
All my RPi, phones and tablets are on Anker. Get them in bulk ya won't regret it.
It also dawned on me I have not had one SD card go bad nor a single bad work unit since I went all Anker about 2 months ago i think.
The Drok was plugged into an Anker USB charger. The cables were plugged into my phone with battery at 76% and screen on.
The measurement should be taken at the phone end of the charging chain to get an idea of the voltage drop AFTER the charging cable. Since the DROK is at the PSU side it measure the voltage before going through the resistance of the charging cable. The current rating is still valid, and you could calculate the voltage drop at your phone if your have a multimeter that can measure the resistance and you could get to the power wires. There are tables online that give the resistance value of stranded copper wiring at various gauges - you would calculate the Vdrop for the 5V line based on size and the Ground line based on size. V=IR!
Anker Powerline uses a 20AWG 5V line and an 18AWG Ground (which I'm dubious of as it's more braided RF shielding cable, so not sure what the REAL 18AWG equivalent would be.
20AWG = .01015ohm/ft
18AWG = .006385ohm/ft
So (1.47A*.01015ohm)+(1.47A*.006385ohm) = .01492V + .009386V = .024V drop (Negligible)
"Standard" USB Cables are 28 gauage for both 5V and power ground
28AWG = .0649ohm/ft
At one foot, that doesn't matter, but a common USB cable is 3ft.
So (1.47A*.0649ohm)*(3ft 5v line + 3ft ground line) = .57V drop! That is quite significant for a Pi!
-You no longer have to hold back ca-certificates if you apt-get update to get the latest openssl package. The issue has been fixed - verified on my pi3-0. Once you have new openssl and have unheld ca-certificates, make sure to reboot your Pi or restart boinc so that it uses the latest openssl libraries.
-Raspbian now automatically expands the filesystem on first boot to fill your SD card - still an option in raspi-config
-If you run the full version of Raspbian Jessy, you can place a wpa-supplicant.conf file in /boot to have the Pi automatically configure wireless. This is helpful if you plan to run the Pi headless as many of us do. Unfortunately, I confirmed last night that this feature is not available for Jessy Lite (BOO!). One of the Pi folks acknowledged that this was a miss and we will hopefully see it added in a future version of Raspbian. More information here: https://www.raspberrypi.org/forums/viewtopic.php?f=28&t=150772&p=990193#p990193
@KF7IJZ I am in
)
@KF7IJZ I am in Nashville.
Grats team on big Milestone!
Looking forward to the video.
@Bikeman - What interesting things is your Pi Zero doing?
RE: @Bikeman - What
)
Currently it's just "burning-in" (E@H), It is supposed to replace the Raspi "1A" of my fish-eye "all-sky" meteor chasing camera (visible in the photo here https://www.raspberrypi.org/forums/download/file.php?id=11239 in the bowl next to the telescope). But for that I have to find the time to solder the IO connector pins to the Pi Zero (it drives a little LCD that idsplay some status information).
Meanwhile it's so hot here in northern Germany that I powered down almost all my crunchers...except for the Pis , of course :-)
as for the team, we have to make sure to celebrate when we brake thru 3.141592*10^6 !!
Cheers
HB
RE: RE: @Bikeman - What
)
Once we break 3 million I'll try and watch the numbers daily and let everyone know when we are close.
I am down to 3 GPUs and 4 cores running at night, plus the RPi. I have fallen from 700K RAC to 200K+ and that is dropping. Depressing. :-(
With shaky hands and blurred vision me plus solder iron could only mean trouble. lol
Cheers!
Update on my Pi 3
)
Update on my Pi 3 Cluster.
I finally got time to spend assembling and filming the assembly of the cluster. My RAC will be dropping as my 1 Pi 3 was offline most of the weekend. I still have lots of the desktop configuration to shoot and I learned two things this morning that will make this even easier - 1) You can apparently now config WiFi from the /boot partition, meaning you don't have to get it online before connecting to WiFi and 2) Apparently the fixed OpenSSL so you no longer have to hold ca-certificates (which I just did a screen cast of last night).
I posted some pictures on Twitter over the weekend:
https://twitter.com/KF7IJZ/status/739151575944306688
https://twitter.com/KF7IJZ/status/739151717263015937
https://twitter.com/KF7IJZ/status/739097805252239360
https://twitter.com/KF7IJZ/status/739181000270307329
So all of the "physical" filming is complete. I now just need to capture screencasts of the setup of the Pis, registration for E@H, and an overall introduction. I also need to record voice over narration for the physical assembly. It will be difficult because the only time it's quiet in my house is after the little ones are asleep! Optimistically, I'd like to be done with this within the week. I also have to be slow and methodical bringing up each node, carefully monitoring temperature because heat rises - hopefully the fans are up to the task!
Thank you to everyone who has supported the team and E@H on the Pi!
My YouTube Channel: https://www.youtube.com/user/KF7IJZ
Follow me on Twitter: https://twitter.com/KF7IJZ
Noticed something last night
)
Noticed something last night on a Pi3 running Ubuntu 16. I was forced to relocate it and after booting I started to notice a small square in the upper right of the desktop appear/disappear. I googled and it stated that was due to a bad power supply or a bad cable. Interesting. In my move I had attached a 1 foot extension cable. I shut the Pi down a removed the 1 ft. cable. No more square. So if you see a small square maybe ....
RE: Noticed something last
)
Specifically, the square is related to low voltage. Most USB Cables do not have large enough power carrying wires inside for large currents (standard USB 2 allowed for 500mW, or 100mA of current - the Pi 3 at full load draws ~4W, 800-1000mA). As current increases, voltage decreases because the wire acts is a resistor. To combat this you can do two things - use short cables or use cables with larger power wires inside. I chose to do both - http://www.amazon.com/Anker-4-Pack-PowerLine-Micro-USB/dp/B015XR60MQ?ie=UTF8&keywords=anker%20powerline%201ft&qid=1465300050&ref_=sr_1_3&sr=8-3
These cables are short and have much larger +5 and Ground wires inside. Most average USB cables were designed around 500mW power handling capabilities.
Additionally, it is also helpful to use a power supply that outputs up to 5.25V, which is still within USB spec. The higher voltage can also combat voltages losses due to small gauge wire or long runs.
My YouTube Channel: https://www.youtube.com/user/KF7IJZ
Follow me on Twitter: https://twitter.com/KF7IJZ
I did some measurements on
)
I did some measurements on some USB cables I had around here. I used this for the measurements. http://www.amazon.com/DROK-Multimeter-Voltmeter-Capacitance-Charging/dp/B00J3JSEG6?ie=UTF8&keywords=droke%20usb&qid=1465351951&ref_=sr_1_sc_1&sr=8-1-spell
The Drok was plugged into an Anker USB charger. The cables were plugged into my phone with battery at 76% and screen on.
Length was by tape measure end to end.
Brand & length A -- V
Anker 12" -- 1.47 - 5.17
Anker 34" -- 1.47 - 5.16
Anker 47" -- 1.47 - 5.16
NoName 28" - 1.35 - 5.18
NoName 32" - .72 -- 5.27
NoName 72" - .76 -- 5.25
NoName 18" - 1.12-1.20 - 5.20
I threw away several that measure badly and the no names are in a box for emergency charging jobs.
All my RPi, phones and tablets are on Anker. Get them in bulk ya won't regret it.
It also dawned on me I have not had one SD card go bad nor a single bad work unit since I went all Anker about 2 months ago i think.
RE: The Drok was plugged
)
The measurement should be taken at the phone end of the charging chain to get an idea of the voltage drop AFTER the charging cable. Since the DROK is at the PSU side it measure the voltage before going through the resistance of the charging cable. The current rating is still valid, and you could calculate the voltage drop at your phone if your have a multimeter that can measure the resistance and you could get to the power wires. There are tables online that give the resistance value of stranded copper wiring at various gauges - you would calculate the Vdrop for the 5V line based on size and the Ground line based on size. V=IR!
Anker Powerline uses a 20AWG 5V line and an 18AWG Ground (which I'm dubious of as it's more braided RF shielding cable, so not sure what the REAL 18AWG equivalent would be.
20AWG = .01015ohm/ft
18AWG = .006385ohm/ft
So (1.47A*.01015ohm)+(1.47A*.006385ohm) = .01492V + .009386V = .024V drop (Negligible)
"Standard" USB Cables are 28 gauage for both 5V and power ground
28AWG = .0649ohm/ft
At one foot, that doesn't matter, but a common USB cable is 3ft.
So (1.47A*.0649ohm)*(3ft 5v line + 3ft ground line) = .57V drop! That is quite significant for a Pi!
Wire resistance values from https://en.wikipedia.org/wiki/American_wire_gauge#cite_note-resft-12
A diagram of the Anker Powerline cables: https://d2c6jjk3vnoatm.cloudfront.net/spree/products/10718/product/A8131011_TD05.jpg?1461127192
My YouTube Channel: https://www.youtube.com/user/KF7IJZ
Follow me on Twitter: https://twitter.com/KF7IJZ
Some Raspbian news that's
)
Some Raspbian news that's useful!
-You no longer have to hold back ca-certificates if you apt-get update to get the latest openssl package. The issue has been fixed - verified on my pi3-0. Once you have new openssl and have unheld ca-certificates, make sure to reboot your Pi or restart boinc so that it uses the latest openssl libraries.
-Raspbian now automatically expands the filesystem on first boot to fill your SD card - still an option in raspi-config
-If you run the full version of Raspbian Jessy, you can place a wpa-supplicant.conf file in /boot to have the Pi automatically configure wireless. This is helpful if you plan to run the Pi headless as many of us do. Unfortunately, I confirmed last night that this feature is not available for Jessy Lite (BOO!). One of the Pi folks acknowledged that this was a miss and we will hopefully see it added in a future version of Raspbian. More information here: https://www.raspberrypi.org/forums/viewtopic.php?f=28&t=150772&p=990193#p990193
My YouTube Channel: https://www.youtube.com/user/KF7IJZ
Follow me on Twitter: https://twitter.com/KF7IJZ
I now have 3 new Pi 3 nodes
)
I now have 3 new Pi 3 nodes online. Will have the full stack of 8 online by this weekend and my video will be ready sometime next week.
My YouTube Channel: https://www.youtube.com/user/KF7IJZ
Follow me on Twitter: https://twitter.com/KF7IJZ