multiplexer

Hi!

I have a Arduino Uno micro-controller. It prvide 6 PWM outputs. I need to extend so I get 16 in total. How can I manage to do this? I've heard a little about multiplexer, but I'm all new in the m-controller game. I hope someone have the time to explain it to me in an easy way taken in to account that this is my first project with a m-controller.

Best regards Erlend

need to extend so I get 16 in total.

For? What you are sending PWM to will influence how you do it.

We're going to make a set of sensores work together with a computerprogram so the computer always know how many of the sensors who have signals. The previous studens implemented 4 of the sensors with the m-controller so there are just 2 inputs left.

You can add some shift registers and drive them with a PWM library http://www.elcojacobs.com/shiftpwm But as Paul says without knowing what you want to do it is hard to say if it is suitable. That answer is insufficient because you don't say what the sensors are.

We're going to make a set of sensores work together with a computerprogram so the computer always know how many of the sensors who have signals.

Very few sensors need PWM [u]input[/u]. You need to tell us more about these special sensors.

do you meen what kind of sensor? it's an Reflective Interrupter in SMT Package SFH 9201

So why do you want a PWM output to them. You will also be needing 16 analogue inputs won't you?

do you meen what kind of sensor?

Yes. That's what we've been asking.

it's an Reflective Interrupter in SMT Package SFH 9201

That link doesn't seem to work. Hint, hint!

http://www.datasheetcatalog.org/datasheet/infineon/1-sfh9201.pdf

OK but that doesn't explain why you think you need a PWM output to drive the LED.

so, what do you suggest?

Assuming this is a reasonably responsive photointerrupter, it would be a very bad idea to drive the emitter with PWM. ;)

The previous studens implemented 4 of the sensors

This implies this was a class exercise.

so, what do you suggest?

Read up what the previous people did. Try and understand what the sensors are all about. Learn that PWM plays no part in driving these. Learn that you need inputs rather than outputs. Try and see if your application needs to control the output of each LED in the reflective sensor. Try and earn your own marks for this project without getting others to do it for you. (that's called cheating)

of course i'll do this without cheating.. But as I said, I've never used a m-controller before. The documentation from the other students are in German, but i'll get someone to translate it for me. I'll be back with further questions later in the project.

The documentation from the other students are in German, but i'll get someone to translate it for me.

What about the code? Do you have that?

yes, I have the code so my task is to get it to work with 16 sensors in total.

yes, I have the code so my task is to get it to work with 16 sensors in total.

I meant for you to post it, so we could see whether the sensors were really being driven with PWM.