MC68HC908LB8CPE Freescale Semiconductor, MC68HC908LB8CPE Datasheet - Page 163

• Manufacturer Part Number: MC68HC908LB8CPE
• Description: IC MCU 8K FLASH 8MHZ 20DIP
• Manufacturer: Freescale Semiconductor
• Series: HC08r

Specifications of MC68HC908LB8CPE

• Core Processor: HC08
• Core Size: 8-Bit
• Speed: 8MHz
• Peripherals: LVR, POR, PWM
• Number Of I /o: 18
• Program Memory Size: 8KB (8K x 8)
• Program Memory Type: FLASH
• Ram Size: 128 x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Data Converters: A/D 7x8b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 20-DIP (0.300", 7.62mm)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Connectivity: -

Chapter 16
Resets and Interrupts
16.1 Introduction
Resets and interrupts are responses to exceptional events during program execution. A reset re-initializes
the microcontroller (MCU) to its startup condition. An interrupt vectors the program counter to a service
routine.
16.2 Resets
A reset immediately returns the MCU to a known startup condition and begins program execution from a
user-defined memory location.
16.2.1 Effects
A reset:
16.2.2 External Reset
A logic 0 applied to RST for a time, t
configured as a reset pin. An external reset sets the PIN bit in the system integration module (SIM) reset
status register.
16.2.3 Internal Reset
Sources:
16.2.3.1 Power-On Reset (POR)
A power-on reset (POR) is an internal reset caused by a positive transition on the V
POR must go below POR rearm voltage (V
a POR. The POR is not a brown-out detector, low-voltage detector, or glitch detector.
A power-on reset:
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Immediately stops the operation of the instruction being executed
Initializes certain control and status bits
Loads the program counter with a user-defined reset vector address from locations $FFFE and
$FFFF
Power-on reset (POR)
Computer operating properly (COP)
Low-power reset circuits
Illegal opcode
Illegal address
Drives the RST pin low during the oscillator stabilization delay
IRL
MC68HC908LB8 Data Sheet, Rev. 1
, generates an external reset when pin PTA5/RST/KB5 is
POR
) to reset the MCU. This distinguishes between a reset and
DD
pin. V
DD
at the
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