External reset, Figure 24), Figure 25 – Rainbow Electronics AT90LS8535 User Manual

Page 23

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23

AT90S/LS8535

1041H–11/01

Figure 24. MCU Start-up, RESET Tied to V

CC

.

Figure 25. MCU Start-up, RESET Controlled Externally

External Reset

An external reset is generated by a low level on the RESET pin. Reset pulses longer
than 50 ns will generate a reset, even if the clock is not running. Shorter pulses are not
guaranteed to generate a reset. When the applied signal reaches the Reset Threshold
Voltage (V

RST

) on its positive edge, the delay timer starts the MCU after the Time-out

period t

TOUT

has expired.

Figure 26. External Reset during Operation

VCC

RESET

TIME-OUT

INTERNAL

RESET

t

TOUT

V

POT

V

RST

VCC

RESET

TIME-OUT

INTERNAL

RESET

t

TOUT

V

POT

V

RST

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