However the transistors are connected to the 5v onboard power, so I expected the output to be at 5V rather than 3.3v is that correct?

I have confirmed the NetDuino is outputting 5v on the 5v onboard output and if I connect the relay directly it works fine.

Any ideas, have I misunderstood something?

Thanks,

Charlie M

I don't quite follow this. Are you connecting the transistors to the 3v3 or the 5v on the Netduino? The Netduino has outputs of 3.3vdc and 5vdc depending on which pin you use.

Also, what is the application with the kettles? When you say kettles, do you mean like teakettles for boiling water?

However the transistors are connected to the 5v onboard power, so I expected the output to be at 5V rather than 3.3v is that correct?

I have confirmed the NetDuino is outputting 5v on the 5v onboard output and if I connect the relay directly it works fine.

Any ideas, have I misunderstood something?

Thanks,

Charlie M

I don't quite follow this. Are you connecting the transistors to the 3v3 or the 5v on the Netduino? The Netduino has outputs of 3.3vdc and 5vdc depending on which pin you use.

Also, what is the application with the kettles? When you say kettles, do you mean like teakettles for boiling water?

---> Edit, I think I follow now. Do you mean you are getting 3.3vdc from the I/O pins? That is what you will get. The I/O pins output 3.3v but are 5v tolerant. See the lower right corner of the spec sheet.


You will need to use the 5v supply pin to power your 5v device.

Oops, I didn't mean to double post! Sorry!

P.S., when it says that the I/O pins are 5v tolerant, it means you can connect a 5v signal input to the pins without damaging them.

I have a 2gb microSD card that I pulled from my Blackberry and I plugged it into my Netduino Plus, and I noticed that it is very slow to read files. It is even slow when using a USB-to-microSD card reader. I am comparing to the speed of a standard USB drive. Are USB read times normally faster than microSD, or am I doing something wrong? Is there a way to read USB drives with a Netduino, i.e. with a compatible USB shield or something? I need faster read times somehow. Even a 20kb file takes too long.

Could be a problem with the SD card... I'm re-formatting it now. I don't have a second one around to try. Perhaps the issue is more related to my code and what I am doing. I am reading a file off of the SD card via a Filestream, and then I am sending the data out onto the Netduino's UART to another device. I am sending it at 1024 bytes at a time, but I wonder if I am running into speed issues because of the fact that I'm re-assembling it for transport onto the UART. The other device also then has to process it. I'm not sure where the bottleneck is. I'd like to think it isn't my code, but that's also possible.