mc68hc908gr8vp Freescale Semiconductor, Inc, mc68hc908gr8vp Datasheet - Page 45

• Manufacturer Part Number: mc68hc908gr8vp
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

4.2.3.3 Low-Voltage Inhibit Reset
A low-voltage inhibit (LVI) reset is an internal reset caused by a drop in the power supply voltage to the
LVI trip voltage, V
An LVI reset:
4.2.3.4 Illegal Opcode Reset
An illegal opcode reset is an internal reset caused by an opcode that is not in the instruction set. An illegal
opcode reset sets the ILOP bit in the SIM reset status register.
If the stop enable bit, STOP, in the mask option register is a logic 0, the STOP instruction causes an illegal
opcode reset.
4.2.3.5 Illegal Address Reset
An illegal address reset is an internal reset caused by opcode fetch from an unmapped address. An illegal
address reset sets the ILAD bit in the SIM reset status register.
A data fetch from an unmapped address does not generate a reset.
4.2.4 SIM Reset Status Register
This read-only register contains flags to show reset sources. All flag bits are automatically cleared
following a read of the register. Reset service can read the SIM reset status register to clear the register
after power-on reset and to determine the source of any subsequent reset.
The register is initialized on powerup as shown with the POR bit set and all other bits cleared. During a
POR or any other internal reset, the RST pin is pulled low. After the pin is released, it will be sampled 32
XCLK cycles later. If the pin is not above a V
addition to whatever other bits are set.
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Holds the clocks to the CPU and modules inactive for an oscillator stabilization delay of 4096
CGMXCLK cycles after the power supply voltage rises to V
Drives the RST pin low for as long as V
delay
Releases the RST pin 32 CGMXCLK cycles after the oscillator stabilization delay
Releases the CPU to begin the reset vector sequence 64 CGMXCLK cycles after the oscillator
stabilization delay
Sets the LVI bit in the SIM reset status register
Only a read of the SIM reset status register clears all reset flags. After
multiple resets from different sources without reading the register, multiple
flags remain set.
TRIPF
.
MC68HC908GR8 • MC68HC908GR4 Data Sheet, Rev. 7
IH
DD
at that time, then the PIN bit in the SRSR may be set in
NOTE
is below V
TRIPF
and during the oscillator stabilization
TRIPF
Resets
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