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STM32F405 breakout board


Just received and built a new board bases on the STM32F405 (Cerberus) MCU. Thought it would help me understand how all the I/O works without the safety net of Gadgeteer. However, as you can see, even the best checked designs are immune to stupid errors. :-[

I had to solder a USB cable to the board as I mis-tracked the USB connector :wall:

Oh well, it only took a couple of hours to find it, but at least it’s programming up now.


I understand what you can feel :-[

Nice board, anyway. Why didn’t you put double rows ? You could have reduced the board’s size ?


The board size wasn’t too much of a concern and the spacing allows me to plug it into my breadboard. The DF Robot board sizes still allow me to get 2 boards per panel and reduce the costs.


@ Jason - You are not alone when it comes to this type of mistakes :wink: Just curious, how is the going with the dimmer control board?


Looks great. I’m just curious why this instead of using an STM32F4 Discovery board? It’s super cheap and the bugs are already worked out.


Where’s the fun in that??? :smiley:


@ RobvanSchelven - I’ve got it working. I was trying to get it to work with a BLE but I need an updated SDK for it. The opto-triacs are zero-volt switching which limit when the switching occurs. I’ve got some random switching opto’s which I hope to try this week.


Got the BLE working from my WP8.1 too now. I just need to tie some mains lights (or something) to the TRIAC board and I’ll post an update.

Not sure I’ll make it to the shed to get what I need today though. Seems like we’re being pounded by a weather front from all directions.


Hi Jason,
Great progress…

would you please share the schematics and the BOM of the switching board through the i would really like to give it a shot :), ii it is going to be Open source of course :wink:



Just received and built a new board bases on the STM32F405 (Cerberus) MCU. [/quote]

I thought of doing the same, just for the sakes of doing it … otherwise I could just buy a Cerb40 or Discovery.



I have bigger plans that include Ethernet, CAN, I2C and multiple connected devices with webservices and SQL or Azure in the backend. Doing it step by step means I can (hopefully) make all my mistakes along the way and not when it’s too late in the game to change them. Hope my approach pays off.


@ Jay Jay, do you mean the Power Switching Triac Board? Let me know and I’ll get it uploaded in the next few days.

I hope to be able to get the WP8.1 source and NETMF source uploaded to CodeShare too for those who are interested. Time permitting I might port the WP8.1 to my Surface too. It would be nice to do a short YouTube video of it all working as well. I see how much time I get.

Keep watching…



Well I’m taking the same approach. I’ve got a board with several different ICs laid out already, but am building tester boards for the individual ICs for that same reason.


I’m hoping to do something similar with bluetooth and some small microcontroller, not sure which ones yet. Size is my most important consideration, has to be very small.


@ Jason - Question, how long did it take you from when you sent out to get the board made to when you figured out the connections were incorrect?


Interesting question. Why do you ask?

Most of my netmf excursions are as a hobbyist so time is not overly important; however my learnt lessons are frequently used in my day job…

Three weeks end to end. Most was spent waiting for the boards to arrive. A couple of hours populating a couple of boards. Another three troubleshooting and attempting a fix and finally five soldering a USB cable to the board.


Yes the power switching Triac :slight_smile: please.


@ Jay Jay - All done. The BOM sections is a bit labour intensity but here it is:

Let me know how you get on.


The Windows RT app was virtually the same code as WP8.1. Works great and here’s the screen gab. Now I just need to decide what to do with all that extra screen space…


Here’s the setup in my shed, testing the four channels from my Surface. The video goes back at the end - all lights are off…