UART is working only when jlink (IAR pod) is connected

[moran]

Posted on August 09, 2015 at 16:02

Hi All,

I'm working on custom board that inlcude stm32l152. I've notice that i can't receive external intterupt on UART3 while JTAG pod is disconnected , why so ? Please advice, Thanks in advance. #uart #jtag-clk

[raptorhal2]

Posted on August 09, 2015 at 16:17

My palm reading says grounding problem.

Without more information on your design, all you will get is speculation, and perhaps not much of that. Cheers, Hal

[moran]

Posted on August 09, 2015 at 16:34

Grounding ? I don't thinks so.

In my main there is while(true) loop that waiting for receiving bytes from UART3 (kind of switch-case). When the JTAG pod is disconnected i can enter the while loop --> i can print debug messages through UART3 but not receive anything. If JTAG pod is connected --> UART3 is working fine ( also the RX = Ext INT ).

[Tesla DeLorean]

Posted on August 09, 2015 at 16:52

The debugger is enabling a clock that you aren't?

[moran]

Posted on August 09, 2015 at 16:58

How can i find it ?

[Tesla DeLorean]

Posted on August 09, 2015 at 17:49

How can i find it ?

Careful static analysis of the source usually works for me. If the code isn't actually running, you'll need to dig a little deeper into the circuit, and the software executed prior to it getting to the configuration code. Up until now you've just described symptoms, which require you to look elsewhere for the cause.