7 years, 6 months ago.

Some guidance: I am confused with mbed

Hello everyone, I am new at this embedded electronics world. I am working hard to learn fast, specially with things related to the Internet of Things. Here is what've done so far, particularly with Bluetooth low energy:

A) I have built my own bluetooth 4 PCBs using Bluegiga's BLE112 modules and have been able to program the Bluegiga's modules with their BGscript b) I have built my own bluetooth 4 PCBs using Nordic nRF51822 from LairdTech's BL600 and have learned their SmartBasic language.

I am comfortable with basic PCB design (eaglecad stuff) and then coding the above modules and playing with Bluetooth low energy stuff.

Unfortunately both BL600 and BLE112 are quite expensive (+ - $16 bucks or so...) So now I want to move towards using cheaper nRF51822 modules that are more barebones such as this one I found for 5 dollars in China: http://see.sl088.com/w/images/a/aa/PTR5518_eng_V1.1.pdf

Anyway, now that I believe I have the nRF51822 module down, I am looking for good/affordable development environment, and when I come across mbed.org I thought I had found everything I need (compiler, community, widely accepted C/C++ ) - But I run into an issue: I simply don't understand how to use mbed.org solutions. I've watched the videos, read all pages over and over, but I still have the following questions:

a) Can I use the compiler and available libraries for any ARM based hardware out there, or only the boards mbed offers?

b) The following link ( http://mbed.org/questions/2718/Using-mbed-compiled-bin-without-mbed-har/ ) confirms that a person can use different Nordic nRF51822 modules with the mbed compiler, because that's how they did it according to the post... but when I tried it, the compiler asks me to add an specific mbed.org hardware platform, and I don't know how I can add a different one, except the one that is coming out in April (http://mbed.org/platforms/Nordic-nRF51822/).

c) Is there a page that can easily explain how to upload code to a board?... The site is not very straight forward in that regard... unless it has to do with mbed platforms only....

I do have the Segger JTAG board – ‘jlink lite’ if that is required to upload code to the boards.

Apologies for rumbling too much here.... I basically would love to start using the mbed development environment with my custom nRF51822 boards, but I have no idea how to start....

I just want to write C code and upload it to my ARM based nRF51822 custom board... is that possible? Any direction is welcomed!

I'd appreciate some guidance and I thank you in advance for the patience.

Regards, Flavio flavio@ortolanos.com

2 Answers

7 years, 6 months ago.

Hello Flavio, writing code and upload is not the way you use the mbed . You use the mbed development platform because of the fast and easy use of the pheriheral libraries behind. The nRF51822 will be supported in near future ... ,so today there is no lib online. The Mbed lib and the hardware interface is published - see http://mbed.org/explore/ . You shoud also keep in mind that you need a working bluetooth stack. The chip itself has no- ? The chinese will sell you a cheap chip, but no working software.

7 years, 4 months ago.

In case anyone is still watching this post, there is now an mbed enabled board for the nRF51822