neděle 22. března 2015

No solar fun on this rainy day

Lazy Sunday here. I slept long, really long. My wife's bed is always so warm when she leaves it that I cannot resist to sneak under her blanket, and this time I fell asleep and woke up at 10AM or even later!
The Sunday wasn't only lazy, but also rainy and dark, not really the day you need when you're playing with solar panels. The ones installed on the balcony generated just a few milliwatts, not worth doing anything with it. I used the LTC3525 I received yesterday, and after a few experiments with coils, I made it work. The mistake was to use the small SMD coil I had at hand, but using bigger, 47uH one helped. The whole setup consists of the 2V solar cell, Schottky diode, 22F goldcap and the LTC chip. Unfortunately the goldcap was drained to 0.7V so it took some time for it to get charged. The power generated by the solar cell on this rainy afternoon was barely able to keep the LTC running without any load, but attaching an Arduino to it was definitely pushing it over the limit, and the voltage begun to drop steadily, mV by mV. To be honest, the Arduino I attached to it wasn't low power at all, it uses LP2981 LDO with something like 100uA of quiescent current, and red power LED with cca 1mA consumption, so I am not that surprised. Let's redo the test with fully charged goldcap, and one of the low power nodes I have.
I modded the meteo node a little. The DHT22 and BMP180 sensors are now powered from Arduino pin, thus I can control their power. The program was changed to not enable the sensors for battery (goldcap) voltages under 3.3V, but the program still needs some tweaking.
While tidying up my desk, I found the 24x2 LCD I bought recently. I had the idea of converting it to a Matrix Orbital compatible display that could be used with Winamp, thus I quickly hacked Arduino to it - just to find out that there's no working plugin! I found "LCDPlugin", but that one is pretty old, and reports that the COM port used for display cannot be accessed. It does work sometimes, but the chances of it working are around 10%. The other plugin is "LCD Smartie", but I don't like the idea of having that program running all the time. As Winamp seems to be dead (the official Winamp page didn't change for years, and just promises something new), I assume it's dead and chances of finding working LCD plugin are close to zero... well, I wonder if there are other players capable of all that Winamp could do, with LCD support. I tried foobar before, but I wasn't impressed at all.

Žádné komentáře: