nrf51 + motion detector only

[terrence]

I need to send data PIR motion detector sensor to the master controller in my motion detector network.
Can I get away with just one of the nrf51 chips and my PIR sensor, or do I need to add an arduino board to receive the data and then instruct the nrf51 to send the data?

[John]

I think a lot depends on the PIR sensor you are using. That said, you could get away with just using the nRF51. We use a simple PIR sensor that just uses a digital I/O to signal motion detected. You could hook it to a GPIO on the nRF51 and set up an interrupt of the proper polarity and then you would know when there was motion.

[terrence]

John thank you for your reply.

Could you tell me which is the lowest cost nRF51 chip that would accomplish this simple task?

Are there boards out there with just a nRF51 chip and a PIR that I could buy?

I am new to this world and am trying to get a prototype system together to prove my concept.

Thank you again for your help. Terrence

[John]

Hi Terrence, I'm not really versed on the pricing of the various nRF51 variants. We chose the nRF51822 based on it's capabilities when coupled with the stack and software Nordic provide. I'm not aware of a board with a nRF51 and PIR available on the commercial market. It would be easy enough to prototype one using a nRF51 development or evaluation kit. They are both available through distributors. We paid about $120 for an development kit. To fully exploit the development kit you also need a nRFgo starter kit which adds to your cost but makes messing with the GPIO much easier. Nordic provides a SDK with example projects for the development and evaluation kits which can get you pretty far down the road in terms of developing a prototype.

[terrence]

Ok, I will look at the dev and eval kits. Thanks for your input.

[ovrebekk]

Hi Terrence

Just for your information we are bringing out a brand new evaluation kit for the nRF51822 these days that has arduino compatible pin headers.

Assuming you can find an arduino based PIR board you might be able to plug it into the new evaluation kit easily.