Printf stop to work only into one task

Hello,

I have a problem with printf function. I have seen the other post about it but I am not sure it's the same issue.

I have a board with a stratix and so nios II. The software has multiple tasks whose one of them is dedicated to monitoring by reading lot of registers and printing their value. We have several hardware designs and the software is ok for all except one. So the problem is probably hardware but what could be the problem's cause ?

So the problem is that at a moment, the monitoring task stop to print the register values. The task continues to be executed since other actions as incrementing a counter are done (this counter is used for pio led). Printf are also ok for all other tasks.

The stdout use uart link to send it to another board. I am not sure but it seems that not reading registers prevents from printf crash into this task. If it's the cause what is the relation between reading registers and using printf.

Thanks