As a weekend engineer, I am trying an experiment with several Raspberry PIs.
For the experiment, I need more than two Raspberry PIs. So I asked persons who are close relationship to borrow them, and some persons accepted my offer.
In this time, I would like to express appreciation for your kindness again.
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Well, I have welcomed to borrow Raspberry PI sufficiently, so it is hard to me to say "if you also have a power adapter and a MicroSD card.....".
So, I went to a "100-Yen discount shop", and bought both a USB battery charger and microUSB cable.
I felt anxiety for the power capacity, however, at least the Raspverry PI2(max Amp 900mA) seems to be working now.
As talked earlier, "The Ebata's home security server" is working by less than the power of LED bulb.
Once, I discussed this issue(low power consumption) with an engineer. He said "That is smart-phones".
Any smart-phone should work without outlet anywhere.
Therefor, the CPU or device developments has progressed to realize power saving, as a result, the merit has spread out other fields.
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When I heard the story, I could thank smart-phone, for the first time.
Now, I was annoyed at using IME of smart-phone, and I become an stressed-out commuter.
The speed of making document is more than one hundred times slower than a PC.