3 Reset management

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3.2.1

RSTOUT pin

RSTOUT signal is used to reset external devices that don’t need initialization before EINIT

instruction of the ST10F27x. In this case, the user can execute some code before initializing the

external device.

The reset circuitry on RSTIN and RPD pins used in this case is the same circuitry described in

the previous section.

3.2.2

Bidirectional reset

The bidirectional reset changes RSTIN pin from a pure input to an open drain output with an

integrated pull-up resistor. This mode is used:

●

to convert software and watchdog resets into hardware resets

●

to provide a reset signal to external devices that can’t be connected to RSTOUT pin

because it’s maintained active during the ST10 initialization.

Pin RSTIN may be connected to external reset devices with an open drain output driver to avoid

conflict.

For more details, refer to the ST10F27x datasheet in the section for “bidirectional reset”.

RSTIN used to reset ST10F27x

RSTOUT used to reset external devices

EINIT