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NUC126
Aug. 08, 2018
Page
210
of 943
Rev 1.03
NUC12
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[27]
CFGXT1
PF[4:3] Multi-Function Select
If user don’t need HXT in his application, he can use CFGXT1 to change PF[4:3] power on
default to GPIO to avoid the effect of crystal oscillator circuite.
0 = PF[4:3] pins are configured as GPIO pins.
1 = PF[4:3] pins are configured as external 4~24 MHz external high speed crystal oscillator
(HXT) pins.
[26]
CFOSC
CPU Clock Source Selection After Reset
The value of CFOSC will be loaded to HCLK (CLK_CLKSEL0[2:0]) in system clock
controller after any reset occurs. HCLK[2:0] = 111 (HIRC) if CFOSC = 1, HCLK[2:0] = 000
(HXT) if CFGSC=0.
0 = 4~24 MHz external high speed crystal oscillator (HXT)
1 = 22.1184 MHz internal high speed RC oscillator (HIRC)
[25:24]
Reserved
Reserved.
[23]
CBODEN
Brown-Out Detector Enable Bit
0= Brown-out detect Enabled after powered on.
1= Brown-out detect Disabled after powered on.
[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]
Reserved
Reserved.
[14:13]
Reserved
Reserved.
[12]
ICELOCK
ICE Lock Bit
This bit only used to disable ICE function. User may use it with LOCK (CONFIG0[1]) bit to
increase security level.
0 = Disable ICE function.
1 = Enable ICE function.
[11]
Reserved
Reserved.
[10]
CIOINI
I/O Initial State Selection
0 = All GPIO set as input tri-state mode after powered on.
1 = All GPIO set as Quasi-bidirectional mode after chip powered on.
[9:8]
Reserved
Reserved.