at89c51re2-slsem ATMEL Corporation, at89c51re2-slsem Datasheet - Page 147

• Manufacturer Part Number: at89c51re2-slsem
• Description: At89c51re2 8-bit Flash Microcontroller
• Manufacturer: ATMEL Corporation

Reset
Introduction
Reset Input
130
AT89C51RE2
The reset sources are : Power Management, Hardware Watchdog, PCA Watchdog and
Reset input.
Figure 45. 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
AT89C51RE2 datasheet.
Figure 46. 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 46. Resistor
b. Power-on Reset
Internal Reset
VDD
+
7663B–8051–03/07
RST