at89c51ac3-s3sim ATMEL Corporation, at89c51ac3-s3sim Datasheet - Page 29

• Manufacturer Part Number: at89c51ac3-s3sim
• Description: At89c51ac3 Enhanced 8-bit Microcontroller With 64kb Flash Memory
• Manufacturer: ATMEL Corporation

Reset
Introduction
Reset Input
4383D–8051–02/08
The reset sources are : Power Management, Hardware Watchdog, PCA Watchdog and
Reset input.
Figure 16. 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
AT89C51AC3 datasheet. The status of the Port pins during reset is detailed in Table 9.
Figure 17. Reset Circuitry and Power-On Reset
RST
RST
a. RST input circuitry
VSS
Watchdog
Watchdog
Hardware
Monitor
Power
PCA
To internal reset
CC
as shown in Figure 17. Resistor
b. Power-on Reset
VDD
+
Internal Reset
RST
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