I've got a load of stuff on order from China. Including shift registers, hopefully they'll do what I want and give me a load of extra pwm capable outputs, I need about 24.
Gosh, that's a lot of PWM outputs. A shift register will give up to 8 outputs from 1 pin but I think you can chain them for more? No idea about PWM with shift registers though.
I'm still waiting for bits. Another Arduino and the wireless transceivers for the clock. Some bits have come quick and others taking long time.
Yeah, I'll no doubt be waiting for the most important part of my bits to arrive last.
I should be able to daisy chain them to add more outputs. 24 PWM outputs needed for that many time zones, but shouldn't need that many due to the map, probably more like 18-20.
Cool, I assume time zones will vary the brightness as the light level changes in each zone.
Exciting to see what parcels have arrived each day, even if some are less exciting things like push buttons and transistors. Sian keeps complaining but nearly all of them have only been 99p. Not actually spent much at all.
Mine isn't going to use an RGB strip. Just some bright white strips for each zone. PWM used to control brightness. Also going to use an LDR to control overall brightness as the RGB one does, so it's not blindingly bright in the dark.
Well, that's the plan, we'll see if I actually manage to sort it.
So far my prototype works for dimming a row of LEDs and using an LDR to change overall brightness, but that's just using regular PWM.
I think I'll initially have the time zones set to dawn/dusk times around spring.
If there's enough space on the arduino I could have a more complete set of times, maybe covering 4 seasons. There's probably a way to calculate this and massively reduce the amount of code but I'm just using set values at the moment.
This doesn't account for the northern hemisphere being different to the southern. That would probably mean I'd need about 72 regions for it to look reasonable - 24 Northern, 24 Equatorial, 24 Southern. I think that would be overkill.
Not a great deal of memory available on the Arduino. Unless you added an SD card to it if the data takes up too much space. How much do you think you'd need for it? How much difference is there between the hemispheres?
Quite a lot then, yes. Worth doing on your map then ;)
Best way would be to use Einsien's equations for general relativity, give the Arduino the spacetime coordinates for the sun and every led on the map, and let it work it out. Simple :D