C515 Datasheet, PDF (16/55 Pages) Siemens Semiconductor Group – 8-Bit CMOS Microcontroller

C515
Reset and System Clock
The reset input is an active low input at pin RESET. Since the reset is synchronized internally, the
RESET pin must be held low for at least two machine cycles (24 oscillator periods) while the
oscillator is running. A pullup resistor is internally connected to V_CC to allow a power-up reset with
an external capacitor only. An automatic reset can be obtained when V_CC is applied by connecting
the RESET pin to V_SS via a capacitor. Figure 6 shows the possible reset circuitries.
a)
b)
&
+
RESET
C515
c)
RESET
C515
Figure 6
Reset Circuitries
+
RESET
C515
MCS03203
Semiconductor Group
16
1997-08-01