New power supply arrived today and it was time to check a couple of numbers for the Odroid setup. The DC-DC converter I have is suppose to take an input voltage from between 20 to 8 VDC. For my solar powered setup there is a chance the battery voltage will be too low to continue to run the Odroid. In this case the Odroid will switch over to a 12 volt supply that comes from power over Ethernet. The Ethernet cable is around 100 feet long and the 12 volts will likely drop as a result. I wanted to be sure that despite the voltage drop the DC-DC converter would continue to supply clean voltage as sufficient current. Knowing the actual power draw of the Odroid this isn't nearly as much of a concern, but I have the tools for this test and it was a good first project for the new power supply.
To test, the power supply is set to 12 VDC and connected to the 12 to 5 volt converter. Monitoring the power output on the oscilloscope, and giving the Odroid a full CPU load I began decreasing the 12 volt input. I could get down to just over 6 volts before the 5 volts output began to sag. Even then the power was clean. So the converter passed this test just fine.
I have worked with a number of variable power supplies as part of my job. I am pretty happy with this one so far. I decided to build a shelve to hold both the supply and my oscilloscope. The heights of my shelves make installing a secondary shelve very functional, and both the power supply and the scope are at a good operating height. It also happens the LED lighting along the top shelve nicely illuminates the test equipment. I also added a strip of LED light under the new shelve. So far I'm pleased with the setup.
I setup the Ordroid to mirror all of DrQue.net through the use of sub-sub-domains. I added this mirror server functionality several months ago by adding CNAME records for each sub-domain of the site that are all routed to the Blue-Dragon
. Right now the Blue-Dragon hosts it's stats page
, proxies ππ
, and all the sub-sub-domain mirrors. I switched the mirrors to the Odroid and verified all of the sites of DrQue.net are functional.
There was one more stress test I wanted to give the Odroid, and that was a heavy floating-point load. The Exynos
processor contains VFP
float-point hardware. I wanted to make use of the SIMD
instructions of the NEON hardware provides and looked into an FFT
unit that would utilize this. I found The Fastest Fourier Transform in the South
(FFTS) but after a lot of work trying to get it to compile I couldn't get it to properly compute an FFT. So I switched to using Fastest Fourier Transform in the West
(FFTW) which I have used many times before. I managed to get a single threaded version to work, but I didn't get the threads working. So I ended up not completing the full test. However, the single threaded version ran with out issue. It just didn't increase power draw much, and barely increased CPU temperature.
The total light for today was the lowest I have ever seen it, registering only 683 Wh/m2
for the entire day. It has been close to overcast with high humidity and haze. Although it rained a little off and on today was far darker than any rainy or cloudy day in my records.