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Chapter 14 Voltage Regulator (S12VREG3V3V5)
MC9S12XDP512 Data Sheet, Rev. 2.17
560
Freescale Semiconductor
14.3.2.3
Autonomous Periodical Interrupt Control Register (VREGAPICL)
The VREGAPICL register allows the configuration of the VREG_3V3 autonomous periodical interrupt
features.
7
6
0
5
0
4
0
3
0
2
1
0
R
W
APICLK
APIFE
APIE
APIF
Reset
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 14-4. Autonomous Periodical Interrupt Control Register (VREGAPICL)
Table 14-4. VREGAPICL Field Descriptions
Field
Description
7
APICLK
Autonomous Periodical Interrupt Clock Select Bit
— Selects the clock source for the API. Writable only if
APIFE = 0; APICLK cannot be changed if APIFE is set by the same write operation.
0 Autonomous periodical interrupt clock used as source.
1 Bus clock used as source.
2
APIFE
Autonomous Periodical Interrupt Feature Enable Bit
— Enables the API feature and starts the API timer
when set.
0 Autonomous periodical interrupt is disabled.
1 Autonomous periodical interrupt is enabled and timer starts running.
1
APIE
Autonomous Periodical Interrupt Enable Bit
0 API interrupt request is disabled.
1 API interrupt will be requested whenever APIF is set.
0
APIF
Autonomous Periodical Interrupt Flag
— APIF is set to 1 when the in the API configured time has elapsed.
This flag can only be cleared by writing a 1 to it. Clearing of the flag has precedence over setting.
Writing a 0 has no effect. If enabled (APIE = 1), APIF causes an interrupt request.
0 API timeout has not yet occurred.
1 API timeout has occurred.