Clock Module
MCF52211 ColdFire® Integrated Microcontroller Reference Manual, Rev. 2
6-14 Freescale Semiconductor

6.7.1.8 Oscillator Control Low Register (OCLR)

The OCLR is used to enable and configure the external oscillator.

IPSBAR
Offset: 0x12_000A (OCHR)
Access: Supervisor read/write
76543210
R
OCOEN STBY
——————
W
Reset: See note1
1The OCOEN reset state is determined during reset configuration.
0000000

Figure 6-8. Oscillator Control High Register (OCHR)

Table 6-12. OCHR Field Descriptions

Field Description
7
OCOEN
On-chip Oscillator Enable bit. This bit enables the relaxation oscillator.
0 Relaxation oscillator is disabled.
1 Relaxation oscillator is enabled.
Note: When switching the clock source to the relaxation oscillator, this bit should be set before
CCLR[OSCSEL] is set.
6
STBY
Relaxation oscillator standby. This bit configures the relaxation oscillator for Standby mode with the output
clock running at 400 kHz.
0 Relaxation oscillator is running in normal mode with an output clock of 8 MHz.
1 Relaxation oscillator is running in standby mode with an output clock of 400 kHz.
5–0 Reserved, should be cleared.
IPSBAR
Offset: 0x12_000B (OCLR)
Access: Supervisor read/write
76543210
R
OSCEN REFS LPEN RANGE
————
W
Reset: See note1
1The OSCEN and REFS reset states are determined during reset configuration.
See note 1110000

Figure 6-9. Oscillator Control Low Register (OCLR)