I'm using a stm32f407vg board. Suddenly I can't download my code
to flash memory. It gives me this error " Debugger - Cortex-M error:
no target connected". In options for target > Debug > Settings
in SW Device tab I see " SWDIO: Error No target connected".
How can I solve this?
Start by testing basic connectivity & comms with ST's ST-Link
* If that doesn't work, then you have a fundamental issue -
nothing to do with Keil;
* If that does work, then the issue is somewhere in your Keil
I assume you are connecting using the on board debugger. If so,
here are some ideas for troubleshooting a ST-Link.
I) Test with a pack example
If the top right of the dialog says "No ST-Link detected", or on
the top left, next to "Unit" the pull down box is empty: - Make sure
there are no Windows USB drivers or board debugger firmware issues.
If not - Swap out USB cables - Don't connect the ST-Link to your
computer via USB hub
If the box on the top left says - "Unknown target connected" - On
the middle-left of the screen, in the 'Target Com" box, switch the
Port from "JTAG" to "SW" - ST-LINK requires a Serial Wire interface,
If that works, close the dialogues. Still using the sample pack
example, Select Debug-> Start/ Stop debug session. If you get a
pop up box, that says