mc68hc908ap8cfa Freescale Semiconductor, Inc, mc68hc908ap8cfa Datasheet - Page 73

• Manufacturer Part Number: mc68hc908ap8cfa
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

5.2.2 TBM Reference Clock Selection
The timebase module reference clock (OSCCLK) is selected by configuring two bits in the CONFIG2
register, at $001D. See
Freescale Semiconductor
OSCSEL1
0
0
1
1
Address:
The internal oscillator is a free running oscillator and is available after each
POR or reset. It is turned-off in stop mode by setting the STOP_ICLKDIS
bit in CONFIG2.
The RCCLK or XCLK is only available if that clock is selected as the CGM
reference clock, whereas the ICLK is always available.
Reset:
Read:
Write:
OSCSEL0
OSCCLK1
0
1
0
1
ICLKDIS
Table 5-2. Timebase Module Reference Clock Selection
STOP_
$001D
0
0
1
1
Bit 7
Chapter 3 Configuration & Mask Option Registers (CONFIG &
0
Figure 5-3. Configuration Register 2 (CONFIG2)
RCLKEN
STOP_
Table 5-1. CGMXCLK Clock Selection
CGMXCLK
6
0
MC68HC908AP Family Data Sheet, Rev. 4
RCCLK
XCLK
ICLK
—
XCLKEN
STOP_
OSCCLK0
5
0
0
1
0
1
OSC2 Pin
output of
Inverting
OSCCLK1 OSCCLK0
NOTE
NOTE
X-TAL
f
f
BUS
BUS
—
4
0
3
0
Not used
Internal oscillator generates the CGMXCLK.
RC oscillator generates the CGMXCLK.
Internal oscillator is available after each POR or
reset.
X-tal oscillator generates the CGMXCLK.
Internal oscillator is available after each POR or
reset.
Timebase Clock Source
Internal oscillator (ICLK)
RC oscillator (RCCLK)
X-tal oscillator (XCLK)
2
0
0
Not used
Comments
1
0
0
SCIBD-
SRC
Bit 0
MOR).
0
Clock Selection
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