Erratic characters with Serial library using G2553

[xv4y 46]

Hi,

 

I think this is more related to the MSP430G2553 than to Energia but I want your opinion.

I am a beginner with all of this so don't be surprised if my questions are stupids.

 

For my project (a beacon generator with an RTC clock) I was using TimerSerial for debugging.

I had no problem at all with it, always had good data coming from the LaunchPad.

 

Then I decided to switch to Serial (the hardware UART) since TimerSerial was generating some delays and possibly making the RTC drift.

Using a simple code (just a clock) with short strings sent every second, no problem.

However, using Serial with my beacon code that generate a lot of text for debugging, the display was totally erratic.

It seems that the hardware UART has a really small buffer and if I send too much data too often it get corrupted and then all the following strings are corrupted.

 

Can someone confirm me this or is it something in my code ?

It is not a big deal indeed since I can switch back to TimerSerial and this display is only for debug, but I would like to understand...

 

Thanks for your help.

Regards,

Yannick.

[jsolarski-backup 22]

Could you post your code?

But it sounds like your sending data to fast to the buffer and overwriting what has not been sent.

[energia 485]

Welcome back xv4y! This sound like a bug somewhere in Energia. Can you please post the complete Sketch?

 

Robert

[xv4y 46]

Hi friends,

 

I could post the code but it is rather long and since the serial things are used only for debugging there is a lot of #IFDEF and it will not be really easy to read.

I will try to post the interesting things anyhow.

However, this is the weekend and I have kids at home until tuesday because it is Trung Thu (Moon day).

 

Robert, if you'd like to try to compile the code I can send it to you via a private message.

 

Thanks for your help!

Yan.

[energia 485]

Feel free to send me the code and I'll try to narrow it down. We can use this thread to further discuss.

[xv4y 46]

Hi,

 

Well, this is just to keep the community informed.

We (in fact mainly Robert) are investigating the problem as it may be a bug in the Serial library.

This could be related to a SRAM exhaustion.

 

If you experience the same kind of anomaly, please report...

 

Regards,

Yannick.

[xv4y 46]

Hi,

 

The problem was all mine. I did a little rework of my code and saved a few bytes of SRAM.

Now the program is running ok with Serial lib for hardware communications.

It seems likely that the memory was exhausted and in some cases Serial could have been using too much SRAM for its buffers and getting corrupted characters.

 

I will soon publish the code in my blog.

 

Regards,

Yan.

---

http://xv4y.radioclub.asia/

[energia 485]

Thanks for the update Yan! If freeing up some RAM made it work then we were probably dealing with the stack growing into an area that was already occupied by preallocated variables aka stack overflow.

 

RObert