ST10F280_12 datasheet(176/239 Pages) STMICROELECTRONICS

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System reset

ST10F280

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Doc ID 8673 Rev. 3

hardware reset. C0 capacitor starts to charge throught R0 and at the end of reset sequence

ST10F280 restarts. RPD pin threshold is typically 2.5V.

Depending on the delay of the next applied reset, the MCU can enter a synchronous reset or

an asynchronous reset. If RPD pin is below 2.5V an asynchronous reset starts, if RPD pin is

above 2.5V a synchronous reset starts. (see Section 17.1: Asynchronous reset (long

hardware reset) and Section 17.2: Synchronous reset (warm reset)).

Note that an internal pull-down is connected to RPD pin and can drive a 100

μA to 200μA

current. This Pull-down is turned on when RSTIN pin is low.

In order to properly use the Bidirectional reset features, the schematic (or equivalent) of

Figure 66 must be implemented. R1-C1 only work for power-on or manual reset in the same

way as explained previously. D1 diode brings a faster discharge of C1 capacitor at power-off

during repetitive switch-on / switch-off sequences. D2 diode performs an OR-wired

connection, it can be replaced with an open drain buffer. R2 resistor may be added to

increase the pull-up current to the open drain in order to get a faster rise time on RSTIN pin

when bidirectional function is activated.

The start-up configurations and some system features are selected on reset sequences as

described in Table and Table 37.

Table 36 describes what is the system configuration latched on PORT0 in the five different

reset ways. Table 37 summarizes the bit state of PORT0 latched in RP0H, SYSCON,

BUSCON0 registers. RPOH register is described in Section 19.2: System configuration

registers.

ST10F280 Datasheet(PDF) 176 Page - STMicroelectronics