Advance Information MC68HC(7)08KH12Rev. 1.1
30 Freescale Semiconductor
1.5.3 Oscillator Pins (OSC1 and OSC2)
The OSC1 and OSC2 pins are the connections for the on-chip oscillator
circuit. (See Section 8. Clock Generator Module (CGM).)
1.5.4 External Reset Pin (RST)
A logic zero on the RST pin forces the MCU to a known start-up state.
RST is bidirectional, allowing a reset of the entire system. It is driven low
when any internal reset source is asserted. The RST pin contains an
internal pullup device. ((See Section 7. System Integration Module
(SIM).)
1.5.5 External Interrupt Pin (IRQ1/VPP)
IRQ1/VPP is an asynchronous external interrupt pin. IRQ1/VPP is also
the OTPROM programming power pin. The IRQ1/VPP pin contain an
internal pullup device. (See Section 14. External Interrupt (IRQ).)
1.5.6 USB Data Pins (DPLUS0–DPLUS4 and DMINUS0–DMINUS4)
DPLUS0–DPLUS4 and DMINUS0–DMINUS4 are the differential data
lines used by the USB module. (See Section 9. Universal Serial Bus
Module (USB).)
1.5.7 Voltage Regulator Out (REGOUT)
REGOUT is the 3.3V output of the on-chip voltage regulator. It is used to
supply the voltage for the external pullup resistor required by the USB on
either DPLUS or DMINUS lines, depending on type of USB function.
REGOUT is also used internally for the USB data driver and the Phase-
locked Loop circuit. The REGOUT pin requires an external bulk
capacitor 1µF or larger and a bypass capacitor. (See Section 9.
Universal Serial Bus Module (USB).)