Starting out

[JAC]

Hi, I've being using an arduino to collect pressure measurements from the BOSCH BMP280 pressure sensor over I2C. I want to do the same using the nRF52840 and miniturize my device. I want to send the data over bluetooth to my PC. Where are the tutorials and sample code that would help me? Is there a sample project similar to this?

[awneil]

devzone.nordicsemi.com/.../introduction-to-bluetooth-low-energy-and-ble-devel

https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.sdk5.v15.3.0/examples.html

[Vidar Berg]

I think it's best to do it in smaller steps, so I would suggest that you start getting the sensor reading over I2C to work first, then once that's done you can start with the BLE part. The TWI Sensor Example can be modified to read data from the bosch sensor. Also, see TWI master for documentation of the driver itself. 

[awneil]

Vidar Berg said:

I think it's best to do it in smaller steps

Absolutely - always !...

Vidar Berg said:

The TWI Sensor Example can be modified to read data from the bosch sensor

before that, use the TWI Scanner Example to verify that you can address the sensor at all.

[JAC]

Thank you both very much for your advice.

Initially, I was also looking at the Thingy:52 as a way of getting something up and running quickly.

Can you tell me if there are an example of adding a sensor to the GPIO and I2C on the Thingy:52. Would the mobile application be capable of showing the data coming through from that sensor?

Is it possible to then evaluate the power consumption?

[awneil]

The Thingy code is not up-to-date - I gave up even trying to get it to build.

[JAC]

That doesn't sound reassuring from a respected company like Nordic!

Are there not a lot of people requesting the same thing?

[Vidar Berg]

The thingy FW is not a part of our regular SDK release. It's built on an older SDK version. Also, it doesn't include project files for Segger Embedded Studio IDE, requiring you to either Makefiles or Keil uVision to build it. It's certainly not the most straightforward example to start with. Again, my advice is to do it in smaller steps. I would have started developing the FW on an nRF52840 DK connected to a BMP280 breakout board (or an Arduino type shield if that exists) and get the I2C part to work first. The development kits, unlike the thingy:52, include an onboard Jlink lite debugger that you can later use to program your custom boards.

Our online power profiler makes it easy to estimate current based on various parameters: https://devzone.nordicsemi.com/nordic/power. It does not include the sensor, but it will likely have little impact on the average power consumption. It depends on how frequent you need an updated reading and what the sensor's standby current is. For actual measurements on the DK, see Measuring current. 

[awneil]

Vidar Berg said:

It's certainly not the most straightforward example to start with

Ha ha - no kidding!!

To be fair, the Thingy is a pretty complex system - certainly not a beginning example!

I wouldn't be surprised to find that most people just buy it and use it as-is ... ?