View Full Version : Solved What pin is the Vdd pin on the 40 pin DIP Prop

SONIC the Hedgehog
01-20-2012, 11:26 PM
So I got my my Propeller education kit a few weeks ago. I understand it great, and I even read over the data sheet. But the only problem I found was that, while the schematic for the demo board is extremely helpful, it uses a quad flat lead package, not dual inline. The part for adding the VGA output was fine, but I would like to add PS/2 mouse and keyboard support, but it says to connect the clock and data pins of the PS/2 output to Vdd, but I don't know what pin that is. And the different packages are supposed to have the same number of I/O pins. Could someone please help?

01-20-2012, 11:54 PM
VDD is the power pin for the chip. (not vin but 3.3v) there are two of them on the prop. You also need to use a resistor not connect directly to the pin, it's called 'pullup'

SONIC the Hedgehog
01-21-2012, 12:27 AM
Ahh that helps a bunch. I thought it was some kind of special pin, but that clears things up alot, thanks!

SONIC the Hedgehog
01-21-2012, 12:32 AM
Thanks a bunch, that helps. So all I need is a resistor, which I assume would be 10 ohms? And a connection that doesn't go strait from the pin? I think I understand now.

01-21-2012, 10:30 AM
Pull-ups are usually more like 4k7 to 10k.

01-21-2012, 11:23 AM
Is this the image you needed?


Duane Degn
01-21-2012, 03:09 PM

I'm not sure what comes with the Propeller Education Kit, but the Propeller Education Kit (pdf) is available from the help window of the Propeller Tool.

As Franklin pointed out, Vdd is 3.3V. When you connect something to Vdd, that doesn't mean you have to connect it to a Vdd pin on the Prop, it just needs to be connected to 3.3V on the breadboard (or some other source). Most of the pull-up resistors I've seen used with the Prop have been 10K Ohm (10,000 Ohm).

Vss is ground.

Duane Degn
01-22-2012, 11:59 PM
I saw in another thread you had concidered purchasing a Hydra system.

I don't know if you know this or not by the Hydra manual is available as a pdf file from the Hydra product page (http://www.parallax.com/StoreSearchResults/tabid/768/txtSearch/Hydra/List/0/SortField/4/ProductID/467/Default.aspx).

The manual has lots of great information about the Propeller especially about using the Props video capability.

SONIC the Hedgehog
01-23-2012, 03:53 PM
Sorry, I meant to reply sooner, but my iPad closed down every time I went to this thread. Thanks for all the he guys.