AT90S/LS4434 and AT90S/LS8535
22
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