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M451
May. 4, 2018
Page
306
of
1006
Rev.2.08
M4
51
S
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NICA
L RE
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R
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NC
E
M
A
NU
A
L
[22:21]
CBOV
Brown-Out Voltage Selection
00 = Brown-out voltage is 2.2V.
01 = Brown-out voltage is 2.7V.
10 = Brown-out voltage is 3.7V.
11 = Brown-out voltage is 4.5V.
[20]
CBORST
Brown-Out Reset Enable Bit
0 = Brown-out reset Enabled after powered on.
1 = Brown-out reset Disabled after powered on.
[19:11]
Reserved
Reserved.
[10]
CIOINI
I/O Initial State Selection
0 = All GPIO set as Quasi-bidirectional mode after chip powered on.
1 = All GPIO set as input tri-state mode after powered on.
[9:8]
Reserved
Reserved.
[7:6]
CBS
Chip Booting Selection
When CBS[0] = 0, the LDROM base address is mapping to 0x100000 and APROM base
address is mapping to 0x0. User could access both APROM and LDROM without boot
switching. In other words, if IAP mode is supported, the code in LDROM and APROM can
be called by each other.
00 = Boot from LDROM with IAP mode.
01 = Boot from LDROM without IAP mode.
10 = Boot from APROM with IAP mode.
11 = Boot from APROM without IAP mode.
Note:
BS (FMC_ISPCTL[ 1]) is only be used to control boot switching when CBS[0] = 1.
VECMAP (FMC_ISPSTS[23:9]) is only be used to remap 0x0~0x1ff when CBS[0] = 0.
[5]
Reserved
Reserved.
[4:3]
CWDTEN[1:0]
Watchdog Timer Hardware Enable Bit
When watchdog timer hardware enable function is enabled, the watchdog enable bit
WDTEN (WDT_CTL[7]) and watchdog reset enable bit RSTEN (WDT_CTL[1]) is set to 1
automatically after power on. The clock source of watchdog timer is force at LIRC and
LIRC can’t be disable.
CWDTEN[2:0]
is CONFIG0[31][4][3],
011 = WDT hardware enable function is active. WDT clock is always on except chip enter
Power-down mode. When chip enter Power-down mode, WDT clock is always on if
CWDTPDEN is 0 or WDT clock is controlled by LIRCEN (CLK_PWRCTL[3]) if
CWDTPDEN is 1. Please refer to bit field description of CWDTPDEN.
111 = WDT hardware enable function is inactive.
Others = WDT hardware enable function is active. WDT clock is always on.
[2]
Reserved
Reserved.
[1]
LOCK
Security Lock Control
0 = Flash memory content is locked.
1 = Flash memory content is not locked.
[0]
DFEN
Data Flash Enable Bit
The Data Flash is shared with APROM, and the base address of Data Flash is decided by
DFBA (CONFIG1[19:0]) when DFEN is 0.
0 = Data Flash Enabled.
1 = Data Flash Disabled.