Are there PWM lines on the Interface Board?

Liam,

On the tutorial page for the Interface Board, there is a paragraph that addresses Servo's and Motors.  However, the sentence tails off without an explanation:

Servos & Motors

There are no servo headers on the Interface Board - you can pretty easily create your own with some 0.1" spaced headers.  The PWM lines on the Interface Board can be found at ...

I'm still a newbie and I'm using Max to communicate with the Controller board.  Are there new Max objects for the Interface board?  

Jonathan

Sorry about that!  That definitely needs to be fixed, but we're busy at the Maker Faire this weekend so I'll have to update it sometime this coming week.  

A quick answer - yes, there are PWM signals available on the Interface Board, but of course there are not high current drivers on them, as with the Application Board.  You can look at the datasheet/schematic for more info on the pin layout of the Interface Board.

Are there any funky issues with the application board v1.0 PWM output? I put mine on the scope and played around with all the various OSC variables and I couldnt get a clean square wave. More importantly my circuit which consists of a mosfet driver and naturally enough a mosfet will for lack of a better word cause the Make Controllers frequency to 'freak out' and stick latched. Im still a newbie so please excuse my lack of proper terms.  Anyway I thought Id start with trying to figure out why i get a nice RISE and but the fall is sloped down instead of a clean drop.

Thanks

Ken

On the App Board, the PWM signals are connected to the enable lines of the output drivers - the outputs drivers themselves put out a signal that goes from high to no connect, which it sounds like is what you might be seeing.  You can solder onto the raw PWM signals I think - they might not be brought out to separate pads.

If that's not your case, could you post some code somewhere (http://www.pastie.org or the like)?

Thanks for the input.. Do you know off hand how much current the raw PWM can handle???.. I took a stab at looking for that in the documentation but Im no expert and Id like to avoid frying something by going this route.

Thanks
Ken

Not much - only a few milliamps.  Unless you're dimming an LED, you'll want something in between the pin and your load.

Thanks for the reply Liam,

  Ok just to wrap it up.. I pulled the H driver chips out and probed the PWM line on the socket for the controller and got a nice clean Pulse up and down! So then i simply figured out which pin from the H driver socket went to the Digital out screw header and used one of those bread board (red colored) one to bring the singal to the screw head. NO soldering required! I can now use this to drive my mosfet driver without any of that weird feedback i was seeing!

Thanks for all your help guys.

Ken