AT89C51ID2-SLSIM Atmel, AT89C51ID2-SLSIM Datasheet - Page 31

• Manufacturer Part Number: AT89C51ID2-SLSIM
• Description: C51ID2 64KF TWI 32KHZ PLCC44 3-5.5V IND.
• Manufacturer: Atmel

Reset
Introduction
Reset Input
4289C–8051–11/05
The reset sources are : Power Management, Hardware Watchdog, PCA Watchdog and
Reset input.
Figure 7. Reset schematic
The Reset input can be used to force a reset pulse longer than the internal reset con-
trolled by the Power Monitor. RST input has a pull-down resistor allowing power-on
reset by simply connecting an external capacitor to V
value and input characteristics are discussed in the Section “DC Characteristics” of the
AT89C51ID2 datasheet.
Figure 8. Reset Circuitry and Power-On Reset
RST
RST
Watchdog
Watchdog
Hardware
a. RST input circuitry
Monitor
VSS
Power
PCA
To internal reset
CC
as shown in Figure 8. Resistor
AT89C51ID2
b. Power-on Reset
Internal Reset
VDD
+
RST
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