jaustin,
I've only done a little PWM work, and that was just to make a few videos. But the first place to start is the datasheets/pinouts.
You didn't mention the board model, which helps a lot, but there are a few basic guidelines for using the ATTiny85 with PWM (which it is great at. First, the pinout (
note purple pins):
...match that up against this good one from SparkFun:
Be very, very mindful of
who calls
which pins
what. Also, as you can see from the above, the Atmel chips can be 'programmed' to use a physical pin for more than one use (usually only one assignment per program).
Question #1:P0 (PB0) can be configured for PWM output. You can see this in the above pinouts, and I actually did exactly this
here, where I used a light sensor (cadmium sulfide cell) to provide an analog controlling voltage to drive a servo with PWM-
with no libraries. All credit for heavy lifting to Nick Crescimanno at Electric Sheep Labs (
the above manual explains every command/register, so you'll know what to tweek).
Question #2:Yes. But you will
not be using it for analog, instead choosing PWM out. There are ways to do this more simply via the Arduino code, but I haven't tried that way. I know that using the Servo.h library is large-something you must mind when fudging with the 'tinys'. Always enable verbose output on compile/upload to see how much room you are using with each 'sketch'.
I looked at a few boards, and they are all the same. Your manual will specify voltage in, and likely wattage out. You then need to do the basic Ohm's Law calcs to figure out the LED side of things... The only thing coming from the '85 will be the PWM out to the (you guessed it) PWM pin on the controller.
Question #3:I will go out on a limb here and suggest that the 5v and Vin pins on the DS do what they normally do, which is 5v for a regulated source, and Vin for an unregulated source (check manual for voltage range), which goes into the ST 78M05
here), which can take a maximum 35vdc(!).
Unless there is a legitimate reason, you might consider powering them both from the same PS, as the 7805 is a switching regulator, and thus very efficient. The ability of your LED controller board to tolerate switched power is covered in that device's manual/datasheet. Look for things like "ripple"...
Question #4:Because there is really nothing special about the Digispark ATTiny85 and any other
ATmel PWM output, you have lots of examples at your fingertips
here...
Question (implied)#5:The experts here have the final word, but there are only 2 ways to fry electronics (aside from defects):
1. Too much voltage where it shouldn't be (includes lightning), and...
2. Too little voltage where it shouldn't be.
The second is only a concern when you are using components that will draw too much current if voltage is too low. Shorting out pins with power is an example. Another example I just did myself is burning out a pot by adjusting it down to where the current passing through it made it like a shunt (2v/1Ω=2amperes), and your power supply has no trouble giving it enough current to fry. Bench supplies can be very accommodating in this way...
If you are tinkering, you will [probably?] never encounter this.
So my guess it you put too much voltage where it shouldn't have been. Before applying any voltage to any pins (including logic), check the datasheet. For the '85,
this answer seems as good as any to me. What is weird is that the '85 (and her sisters) all have 3 pin protection
in them. Have you considered the possibility of a blown 7805? They are drop-dead easy to check:
HTH!
pat
The ATTiny85 is to me an astonishing achievement. Keep this link bookmarked to investigate what happens under the hood with PWM and the comparators:
ATTiny Datasheet. In fact, because you are using an ATTiny where there isn't as much room for large libraries, this URL will show you how to make the chip do anything you like-
directly. Microchip, who for better or worse bought Atmel, gives this URL as your starting page to go as deep as you need to:
ATTiny Start Page
