saf-xc878m-16ffi5v Infineon Technologies Corporation, saf-xc878m-16ffi5v Datasheet - Page 80

• Manufacturer Part Number: saf-xc878m-16ffi5v
• Description: 8-bit Single-chip Microcontroller
• Manufacturer: Infineon Technologies Corporation

3.7
The XC87x has five types of reset: power-on reset, hardware reset, watchdog timer
reset, power-down wake-up reset, and brownout reset.
When the XC87x is first powered up, the status of certain pins (see
defined to ensure proper start operation of the device. At the end of a reset sequence,
the sampled values are latched to select the desired boot option, which cannot be
modified until the next power-on reset or hardware reset. This guarantees stable
conditions during the normal operation of the device.
The second type of reset in XC87x is the hardware reset. This reset function can be used
during normal operation or when the chip is in power-down mode. A reset input pin
RESET is provided for the hardware reset.
The Watchdog Timer (WDT) module is also capable of resetting the device if it detects
a malfunction in the system.
Another type of reset that needs to be detected is a reset while the device is in
power-down mode (wake-up reset). While the contents of the static RAM are undefined
after a power-on reset, they are well defined after a wake-up reset from power-down
mode.
3.7.1
Table 24
functions. The symbol “ ” signifies that the particular function is reset to its default state.
Table 24
Module/
Function
CPU Core
Peripherals
On-Chip
Static RAM
Oscillator,
PLL
Port Pins
EVR
FLASH
NMI
Data Sheet
lists the functions of the XC87x and the various reset types that affect these
Reset Control
Module Reset Behavior
Effect of Reset on Device Functions
Wake-Up
Reset
Not affected,
Reliable
The voltage
regulator is
switched on
Disabled
Watchdog
Reset
Not affected,
Reliable
Not affected
Not affected Not affected
Disabled
73
Hardware
Reset
Not affected,
Reliable
Power-On
Reset
Affected, un-
reliable
Functional Description
Table
Brownout
Reset
Affected, un-
reliable
XC87xCLM
V1.5, 2011-03
25) must be