Telecom Design TD1204 have really limited number of GPIOs available even if it have many pins 🙁 … So you quickly have to use the DB2-DB3 pin that are usually used by SWD port.

If you try to reconfigure directly the Pin, this will not work until you inactivate SWD. For this, you must call first the following functions :

GPIO_DbgSWDIOEnable(false);
GPIO_DbgSWDClkEnable(false);

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