Chapter 17 Voltage Regulator (S12VREG3V3V5)
MC9S12XDP512 Data Sheet, Rev. 2.11
740 Freescale Semiconductor
17.3.2.3 Autonomous Periodical Interrupt Control Register (VREGAPICL)

The VREGAPICL register allows the configuration of the VREG_3V3 autonomous periodical interrupt

features.

Module Base + 0x_02
76543210
RAPICLK 0000
APIFE APIE APIF
W
Reset 00000000
= Unimplemented or Reserved

Figure 17-4. Autonomous Periodical Interrupt Control Register (VREGAPICL)

Table 17-4. 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.