PXR40RM Datasheet, PDF (144/1434 Pages) Freescale Semiconductor, Inc – PXR40 Microcontroller

Power Management Controller (PMC)
5.4.3 Status Register (PMC_SR)
The status register contains interrupt flag bits for the LVD monitors.
Offset: PMC_BASE + 0x0008
0
R0
W
Reset 0
1
2
3
4
5
6
7
8
9
0
00
0
LVF
STBY
BGRDY BGTS
0
0
0
00
0
u¹
0 00
10 11
00
00
Access: User
read/write
12
13 14 15
0
LVFC
STBY
0
0
w1c
0 0 00
16
17
18
19
20
21
22
R
LVFCR
LVFCH
LVFC
50
LVFC
33
LVFCC
LVFCA
0
W w1c w1c w1c w1c w1c w1c
Reset 0
0
00
0
0
0
23
24
25 26 27 28
29 30 31
0
LVFR
LVFH
LVF
50
LVF
33
LVFC
LVFA
0
0
0 0 0 0 0 0 0 00
Figure 5-4. Status Register (PMC_SR)
1 _{Reset value depends on whether RAM standby regulator switch reported a brownout condition.}
Table 5-6. PMC_SR Field Descriptions
Field
Description
0–4 Reserved
5
LVFSTBY
Standby-RAM-supply low-voltage flag. This read-only bit indicates that a brownout condition was reported
by the RAM standby regulator switch. Software can clear this bit by writing ‘1’ to the LVFCSTBY bit.
0 No occurrence.
1 LVD occurrence, or brownout, reported by the RAM standby regulator switch.
6
BGRDY
Bandgap ready. This read-only bit gets asserted when the PMC bandgap circuit has finished its startup
procedure during power-up. The PMC LVDs are disabled (output negated) while BGRDY is negated.
0 Bandgap not ready. PMC LVDs disabled.
1 Bandgap ready. PMC LVDs enabled.
7
BGTS
Bandgap temperature status. This read-only bit stores bandgap temperature status.
0 Temperature out of range. Above 160 C.
1 Temperature in range. Below 160 C.
8–12 Reserved
13
Standby-RAM-supply LVF clear. This write-only bit is used to clear the low-voltage flag reported by the RAM
LVFCSTBY standby regulator switch. Writing 1 to this bit informs the RAM standby regulator switch to clear LVFSTBY.
Writing 0 has no effect. Reading this bit always returns 0.
0 No effect.
1 Clears LVFSTBY.
14–15 Reserved
16
LVFCR
Reset-pin-supply LVF clear. This write-only bit is used to clear the low-voltage flag associated with the supply
of the I/O segment that contains the reset pin. Writing 1 to this bit clears LVFR. Writing 0 has no effect.
Reading this bit always returns 0.
0 No effect.
1 Clears LVFR.
5-12
PXR40 Microcontroller Reference Manual, Rev. 1
Freescale Semiconductor