
S12 Clock, Reset and Power Management Unit (S12CPMU)
S12P-Family Reference Manual, Rev. 1.13
226
Freescale Semiconductor
7.3.2.17
Autonomous Periodical Interrupt Rate High and Low Register
(CPMUAPIRH / CPMUAPIRL)
The CPMUAPIRH and CPMUAPIRL registers allow the conguration of the autonomous periodical
interrupt rate.
Read: Anytime
Write: If APIFE=0, then write anytime, else writes have no effect.
The period can be calculated as follows depending on logical value of the APICLK bit:
APICLK=0: Period = 2*(APIR[15:0] + 1) * fACLK
APICLK=1: Period = 2*(APIR[15:0] + 1) * Bus Clock period
0x02F4
76543210
R
APIR15
APIR14
APIR13
APIR12
APIR11
APIR10
APIR9
APIR8
W
Reset
00000000
= Unimplemented or Reserved
Figure 7-21. Autonomous Periodical Interrupt Rate High Register (CPMUAPIRH)
0x02F5
76543210
R
APIR7
APIR6
APIR5
APIR4
APIR3
APIR2
APIR1
APIR0
W
Reset
00000000
Figure 7-22. Autonomous Periodical Interrupt Rate Low Register (CPMUAPIRL)
Table 7-18. CPMUAPIRH / CPMUAPIRL Field Descriptions
Field
Description
15-0
APIR[15:0]
Autonomous Periodical Interrupt Rate Bits — These bits dene the time-out period of the API. See
Table 7-19 for details of the effect of the autonomous periodical interrupt rate bits.