MC68HC908QY2 MOTOROLA [Motorola, Inc], MC68HC908QY2 Datasheet - Page 111

• Manufacturer Part Number: MC68HC908QY2
• Description: Microcontrollers
• Manufacturer: MOTOROLA [Motorola, Inc]

8.9 Input/Output (I/O) Registers
8.9.1 Oscillator Status Register
MOTOROLA
MC68HC908QY4•MC68HC908QT4•MC68HC908QY2•MC68HC908QT2•MC68HC908QY1•MC68HC908QT1
Address:
The oscillator module contains these two registers:
The oscillator status register (OSCSTAT) contains the bits for switching
from internal to external clock sources
ECGON — External Clock Generator On Bit
ECGST — External Clock Status Bit
Reset:
Read:
Write:
1. Oscillator status register (OSCSTAT)
2. Oscillator trim register (OSCTRIM)
This read/write bit enables external clock generator, so that the
switching process can be initiated. This bit is forced low during reset.
This bit is ignored in monitor mode with the internal oscillator
bypassed, PTM or CTM mode.
This read-only bit indicates whether or not an external clock source is
engaged to drive the system clock.
1 = External clock generator enabled
0 = External clock generator disabled
1 = An external clock source engaged
0 = An external clock source disengaged
$0036
Figure 8-3. Oscillator Status Register (OSCSTAT)
Bit 7
R
0
R
Oscillator Module (OSC)
= Reserved
6
R
0
R
5
0
R
0
4
R
3
0
Input/Output (I/O) Registers
R
2
0
Oscillator Module (OSC)
ECGON
1
0
ECGST
Bit 0
0
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