Chapter 4 Clock Description
MPC5602P Microcontroller Reference Manual, Rev. 4
Freescale Semiconductor
101
4.9.4.2
Frequency Display Register (CMU_0_FDR)
4.9.4.3
High Frequency Reference Register FMPLL_0 (CMU_0_HFREFR_A)
Address: Base + 0x0004
Access: User read-only
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
R
0
0
0
0
0
0
0
0
0
0
0
0
FD[19:16]
W
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
R
FD[15:0]
W
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Figure 4-13. Frequency Display Register (CMU_0_FDR)
Table 4-12. CMU_0_FDR field descriptions
Field
Description
FD[19:0]
Measured frequency bits
This register displays the measured frequency f
RC
with respect to f
OSC
. The measured value is given
by the following formula: f
RC
= (f
OSC
× MD) / n, where n is the value in CMU_FDR.
Address: Base + 0x0008
Access: User read/write
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
R
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
R
0
0
0
0
HFREF[11:0]
W
Reset
0
0
0
0
1
1
1
1
1
1
1
1
1
1
1
1
Figure 4-14. High Frequency Reference register FMPLL_0 (CMU_0_HFREFR_A)
Table 4-13. CMU_0_HFREFR_A field descriptions
Field
Description
HFREF_A
High Frequency reference value
These bits determine the high reference value for the FMPLL_0 clock. The reference value is given by:
(HFREF_A[11:0]/16) × (f
RC
/4).