MC68HC908JB8JDW Freescale Semiconductor, MC68HC908JB8JDW Datasheet - Page 100

• Manufacturer Part Number: MC68HC908JB8JDW
• Description: IC MCU 8K FLASH 3MHZ 20-SOIC
• Manufacturer: Freescale Semiconductor
• Series: HC08r

Specifications of MC68HC908JB8JDW

• Core Processor: HC08
• Core Size: 8-Bit
• Speed: 3MHz
• Connectivity: USB
• Peripherals: LVD, POR, PWM
• Number Of I /o: 13
• Program Memory Size: 8KB (8K x 8)
• Program Memory Type: FLASH
• Ram Size: 256 x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 20-SOIC (7.5mm Width)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Data Converters: -

System Integration Module (SIM)
8.4.2.1 Power-On Reset
Technical Data
100
OSCXCLK
OSCOUT
PORRST
OSC1
RST
IAB
When power is first applied to the MCU, the power-on reset module
(POR) generates a pulse to indicate that power-on has occurred. The
external reset pin (RST) is held low while the SIM counter counts out
4096 OSCXCLK cycles. Sixty-four OSCXCLK cycles later, the CPU and
memories are released from reset to allow the reset vector sequence to
occur.
At power-on, the following events occur:
CYCLES
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•
•
•
•
•
4096
A POR pulse is generated.
The internal reset signal is asserted.
The SIM enables the oscillator to drive OSCXCLK.
Internal clocks to the CPU and modules are held inactive for 4096
OSCXCLK cycles to allow stabilization of the oscillator.
The RST pin is driven low during the oscillator stabilization time.
The POR bit of the reset status register (RSR) is set and all other
bits in the register are cleared.
Figure 8-7. POR Recovery
System Integration Module (SIM)
CYCLES
32
MC68HC908JB8•MC68HC08JB8•MC68HC08JT8 — Rev. 2.3
CYCLES
32
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