System Reset; Reset Source; Power-On Reset (Por) - CMOSTEK CMT2380F17 Manual

12 System Reset

During reset, all I/O Registers are set to their initial values, and the program starts execution from the
Reset Vector, 0000H, or ISP start address by OR setting. The CMT2380F17 has 7 sources of reset: power-on
reset, external reset, software reset, illegal address reset, brown-out reset 0, brown-out reset 1 and WDT
reset. Figure 12–1 shows the system reset source in CMT2380F17.
The following sections describe the reset happened source and corresponding control registers and
indicating flags.

12.1 Reset Source

Power -On Reset
External Reset
Software Reset
Illegal Addr. Reset
BOD0 Triggered
BOD1 Triggered
WDT Overflow

12.2 Power-On Reset (POR)

Power-on reset (POR) is used to internally reset the CPU during power-up. The CPU will keep in reset
state and will not start to work until the VDD power rises above the voltage of Power-On Reset. And, the reset
state is activated again whenever the VDD power falls below the POR voltage. During a power cycle, VDD
must fall below the POR voltage before power is reapplied in order to ensure a power-on reset.
POF0
EXRF
SWRF
Brown-Out Reset0
BO0RE
(PCON2.1)
Brown-Out Reset1
BO1RE
(PCON2.3)
WDT Rese t
WREN
(WDTCR.7)
Figure 12-1. System Reset Source
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CMT2380F17
Internal Reset
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