STC8 microcontroller P5.4 / RST pin functionality

STC8 microcontrollers have P5.4 which can (optionally) be used as device reset pin.

STC calls is a low-level reset pin, but in more standard terminology, it is an active-low reset pin

In order to select between using P5.4 as a ~RST pin or just a GPIO port (P5.4), set or unset bit P54RST (bit 4) in the RSTCFG register.

 

Source: STC8G Datasheet, section 6.3.3+