Datasheet

Chapter 23 Voltage Regulator (S12VREGL3V3V1)
MC9S12XE-Family Reference Manual Rev. 1.25
Freescale Semiconductor 823
23.3.2.4 Autonomous Periodical Interrupt Trimming Register (VREGAPITR)
The VREGAPITR register allows to trim the API timeout period.
23.3.2.5 Autonomous Periodical Interrupt Rate High and Low Register
(VREGAPIRH / VREGAPIRL)
The VREGAPIRH and VREGAPIRL register allows the configuration of the VREG_3V3 autonomous
periodical interrupt rate.
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.
0x02F3
76543210
R
APITR5 APITR4 APITR3 APITR2 APITR1 APITR0
00
W
Reset 0
1
0
1
0
1
0
1
0
1
0
1
00
1. Reset value is either 0 or preset by factory. See Section 1 (Device Overview) for details.
= Unimplemented or Reserved
Figure 23-5. Autonomous Periodical Interrupt Trimming Register (VREGAPITR)
Table 23-6. VREGAPITR Field Descriptions
Field Description
7–2
APITR[5:0]
Autonomous Periodical Interrupt Period Trimming Bits — See Table 23-7 for trimming effects.
Table 23-7. Trimming Effect of APIT
Bit Trimming Effect
APITR[5] Increases period
APITR[4] Decreases period less than APITR[5] increased it
APITR[3] Decreases period less than APITR[4]
APITR[2] Decreases period less than APITR[3]
APITR[1] Decreases period less than APITR[2]
APITR[0] Decreases period less than APITR[1]
Table 23-5. VREGAPICL Field Descriptions (continued)
Field Description