> 20. | GPIO Commands

> This chapter describes the AT commands needed to access and configure the GPIO pins of the TC65.
> Please also refer to [2] for electrical specifications of the GPIOs and their signal states after startup and during application.
> Except for the pulse counter commands, usage of all GPIO commands is restricted to the same interface where the GPIO driver was openend with AT^SPIO. Any attempt to access GPIOs from another interface will be denied with an error message.
> When the TC65 starts up, all GPIO pins are set to high-impedance state after initializing. Therefore, it is recommended to connect pull-up or pull-down resistors to all GPIO pins you want to use as output. This is necessary to keep these pins from floating or driving any external devices before all settings are done by AT command (at least AT^SPIO, AT^SCPIN), and after closing the GPIOs again.