MC9RS08KA2_08 Datasheet, PDF (78/136 Pages) Freescale Semiconductor, Inc – RS08 Microcontrollers

Internal Clock Source (RS08ICSV1)
7
6
5
4
3
2
R
0
0
0
0
0
CLKS
W
Reset:
0
0
0
0
0
0
= Unimplemented
Figure 9-3. ICS Control Register 1 (ICSC1)
1
0
0
IREFSTEN
0
0
Table 9-2. ICSC1 Field Descriptions
Field
Description
6
CLKS
Clock Source Select — Selects the clock source that controls the bus frequency. The actual bus frequency
depends on the value of the BDIV bits.
0 Output of FLL is selected
1 Internal reference clock is selected
0
IREFSTEN
Internal Reference Stop Enable — Controls whether the internal reference clock remains enabled when the
ICS enters stop mode.
1 Internal reference clock remains enabled in stop
0 Internal reference clock is disabled in stop
9.3.2 ICS Control Register 2 (ICSC2)
7
6
5
4
3
2
1
0
R
BDIV
W
0
0
0
0
0
LP
Reset:
0
1
0
0
0
0
0
0
= Unimplemented
Figure 9-4. ICS Control Register 2 (ICSC2)
Table 9-3. ICSC2 Field Descriptions
Field
7:6
BDIV
3
LP
Description
Bus Frequency Divider — Selects the amount to divide down the clock source selected by the CLKS bit. This
controls the bus frequency.
00 Encoding 0 — Divides selected clock by 1
01 Encoding 1 — Divides selected clock by 2 (reset default)
10 Encoding 2 — Divides selected clock by 4
11 Encoding 3 — Divides selected clock by 8
Low Power Select — Controls whether the FLL is disabled in FLL bypassed modes.
1 FLL is disabled in bypass modes
0 FLL is not disabled in bypass mode
MC9RS08KA2 Series Data Sheet, Rev. 4
78
Freescale Semiconductor