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Who to contact if we want to contribute to stm32f4 .net porting


as subject.

the web says people are wanted, but no hints or links how to apply…



Just say what you are working on and when you are ready let everybosy know. Welcome to the forum.


This is what the beta section is about so you started in the right place. We need I2C tested and fixed for example.

Welcome to the community.


I thought Rajesh got it working already.


Well we are working on something [soon to be public] but rigth now we are doing the simplest thing, trying to get the build working using 4.2 and GCC and it seems to be long way to go, as much as i understand all the available code does not all support compiling with GCC :(, all the .S files needed are not for GCC, well working on… trying to convert them for GCC friendliness

hm… we can do a lot of work here, but as soon as we get some build running…

we are testing I2C ourself using different tools/build environements and well there are problems…

ST example for I2C seems NOT TO work

nuttx 6.16 also does not work, when doing i2c bus scan for attached devices
then as soon as first i2c device responds then there come timeout… we have not yet
digged deep enough there, it can be issue with nuttx libraries

funnily st demo code also did not wanted to work out of box



Check this thread.We made a lot of progress there:

It is not completed though (free time is an issue, as always)


I know there are many Antti’s in the world, but is this Antti Lukats?


iam :slight_smile:


Antti - I used Simmsticks for a long time which you were credited with the initial design! Welcome!


well I was the sole author of the SimmStick™ … it got somehow forgotten.

and hm, trying a comeback with some a lot cooler, this is why i struggle wiht netmf right now



@ Architect

I started working on a fix for trying to free up the I2C pins from not being open drain when the application does not use I2C.

I did put a fix in place but seems to muck up I2C.

I am going to forget the open drain for now and concentrate on fixing the core I2C functionality.

Will post if there is any improvement.


Timing issues with Discovery and Cerberus firmware.

Not sure if I am doing something wrong - but I followed the wiki on how to mod the discovery board. With some help from the forum and the tutorials have managed to interface with the built in LEDs, button and do some basic interupt testing. So far so good,…almost:

One thing I noticed when doing blink examples is that when I do Thread.Sleep(X) - The program actually waits for twice as long. So if I use 30000 I get a full minute delay, seems to scale consistently 1000 results in 2 seconds, 60000 results in 2 minutes.

Is there a setting in VS.NET that I need to configure somewhere to indicate the clock on the board? Thanks for any help - Still learning here


This is known issue and we fixed it already in the coming SDK in the next few days/weeks.


Does the fix for double length Thread.Sleep also address the issue where the Cerberus locks up after awhile of sleeping?

long i = 0;
while (true)

Where n =1, The board locks up after approximately 5,700,000 iterations.
Where n = 2, I only tried once and it locked up at 1,800,000 iterations.
Where n = 100, again only a single test and it locked up after 42,000 iterations.

Remove the Thread.Sleep and insert some pin toggling and it will run for many days, I gave up waiting to see if it would lock up.

These results happen on 2 Cerb40 boards and an STM32F4 Discovery board with the hardware modifications applied and the Cerberus firmware flashed.

I’ll be looking at the source code soon, but was hoping this had already been noticed and was being fixed.


The fix was for the wrong timing.


I think the fix was posted in one of the threads recently.


If you are referring to the timing issue (and not the lockup) any chance you can point me that way (or suggest a search keyword.) I read through all the search results for Timer and Thread.Sleep and Discovery but couldn’t find any relevant results/fixes.

Maybe a sticky thread to track Cerberus Known Issues and fixes would be helpful (I’m assuming this isn’t Discovery specific)


Will do with next release very soon. Current one is for preview purposes only.