s908ey8ad4cfjer Freescale Semiconductor, Inc, s908ey8ad4cfjer Datasheet - Page 23

• Manufacturer Part Number: s908ey8ad4cfjer
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

1.5.2 Oscillator Pins (PTC4/OSC1 and PTC3/OSC2)
The OSC1 and OSC2 pins are available through programming options in the configuration register. These
pins then become the connections to an external clock source or crystal/ceramic resonator.
When selecting PTC4 and PTC3 as I/O, OSC1 and OSC2 functions are not available.
1.5.3 External Reset Pin (RST)
A logic 0 on the RST pin forces the MCU to a known startup state. RST is bidirectional, allowing a reset
of the entire system. It is driven low when any internal reset source is asserted. This pin contains an
internal pullup resistor that is always activated, even when the reset pin is pulled low. See
System Integration Module
1.5.4 External Interrupt Pin (IRQ)
IRQ is an asynchronous external interrupt pin. This pin contains an internal pullup resistor that is always
activated, even when the IRQ pin is pulled low. See
1.5.5 Analog Power Supply/Reference Pins (V
V
pins should be as per the digital supply.
See
Freescale Semiconductor
DDA
Chapter 3 Analog-to-Digital Converter (ADC)
and V
SSA
V
same potential as V
V
same potential as V
are the power supply pins for the analog-to-digital converter (ADC). Decoupling of these
REFH
REFL
is the low reference supply for the ADC. V
is the high reference supply for the ADC. V
Note: Component values shown represent typical applications.
(SIM).
MC68HC908EY16 • MC68HC908EY8 Data Sheet, Rev. 10
Figure 1-3. Power Supply Bypassing
DD
SS
V
via separate traces.
via separate traces.
DD
V
DD
NOTE
0.1 µF
Module.
+
MCU
C1
C2
Chapter 9 External Interrupt
DDA
, V
REFH
SSA
DDA
V
, V
SS
should be tied to the
should be tied to the
SSA
and V
(IRQ).
REFL
)
Chapter 14
Pin Functions
23