View Full Version : PWMpal compatible with BS2p40 Module?

09-24-2008, 10:15 AM

I would like to know if I could use the PWMpal with a BS2p40 module. As far as I can tell, all of the necessary pins will line up. Physically I am unsure as I can not find pin layout dimensions. However, I believe the width is the same as a standard module and the pins should still be on a .1" spacing.

I am aware that I would need a socket to support the pins not being used by the PWMpal. I simply need more IO's than a standard BS2 module and also would like to use the PWMpal as well. Thank

Mike Green
09-24-2008, 10:58 AM
You can use the PWMpal with a BS2p40, just not mounted underneath the Stamp. You can run the power, ground, reset, and P0 control line from the PWMpal to really any BS2p40 I/O pin. You don't need to connect the other PWMpal inputs and outputs to the Stamp therefore making the corresponding I/O pins on the Stamp available for other uses.

09-24-2008, 11:56 AM

Thanks, that makes sense. I have a follow-up question if you don't mind, I read through the PWMpal manual a few times but I'm still a bit confused.

Lets say I want to use the PWMpal traditionally installed with a BS2 module on top to control 4 motors simultaneously. From my understanding this would take p12-p15 of the BS2 module out of commission, at least while the pwm signals are active. However, if I mounted the PWMpal alone only connecting power, ground, reset, and P0, would it still have the same function? It seems that in that way I would be able to still use pins p12-p15 as inputs while the pwm signals were being transmitted.

Please correct me if I'm wrong, thanks!!!

Mike Green
09-24-2008, 12:03 PM
If you mount the PWMpal separately from the BS2 and just connect power, ground, reset, and P0, then P8-P15 of the BS2 are available for other uses when the PWMpal output (P12-15) and input pins (P8-11) are in use.

The reason the piggyback mounting scheme was done this way was for ease of use in situations where I/O pins 8-15 on the Stamp were not needed, but the functionality of the PWMpal was needed. You could (of course) use only some of these pins (like output only or only some of the output channels) and the Stamp could then use the pins unused by the PWMpal.

09-24-2008, 12:21 PM

Thank you for your reply. If that is the case, then I may not need a BS2p40. Thanks that makes things a bit easier and cheaper lol.