SWD programming / debug interface on the STM32L073 - SWO??

[MGree.11]

The STM32 STM32L0x3 ref manual (RM073) and STM32L073 datasheet both show only 2 pins for the SWD programming interface:

- PA13 (SWDIO)

- PA14 (SWCLK)

But the schematic for the STM32L073 Nucelo PCB shows PB3 connected as SWO.

I dont see any reference to PB3 being part of the debug interface in the STM32L073 reference manual, datasheet or Cube MX configuration software.

Is PB3 part of the debug interface or not?

Please advise.

[Tesla DeLorean]

NOT supported on CM0(+) devices, board used for several parts.

[Tesla DeLorean]

The "Debug Communications Channel" can be implemented via an "Event Recorder" method

https://www.keil.com/pack/doc/compiler/EventRecorder/html/er_use.html

https://www.keil.com/pack/doc/compiler/RetargetIO/html/_retarget__examples_er.html

ST has a free license for Keil on CM0(+) devices

[MGree.11]

Hi Clive, So I only need to connect power, ground, PA13, PA14 & Reset for programming and debug? Thanks, Mark. Get Outlook for Android<>

[Tesla DeLorean]

That is correct.

For the external ST-LINK/V2 you'll need power, otherwise not, but suggest exposing to a header or test-points

As I recall the PA13/PA14 on the L0 can support a UART if you need to monitor telemetry without a debug pod attached.

[MGree.11]

Brilliant. Thanks Clive. Get Outlook for Android<>