NuMicro® NUC029LEE/NUC029SEE
32-bit Arm
®
Cortex
®
-M0 Microcontroller
Aug, 2018
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System Controllers Space (0xE000_E000 ~ 0xE000_EFFF)
0xE000_E010
– 0xE000_E0FF
SCS_BA
System Timer Control Registers
0xE000_E100
– 0xE000_ECFF
SCS_BA
External Interrupt Controller Control Registers
0xE000_ED00
– 0xE000_ED8F
SCS_BA
System Control Registers
Table 6.2-1 Address Space Assignments for On-Chip Controllers
6.2.5 Register Lock
Some of the system control registers need to be protected to avoid inadvertent write and disturb the
chip operation. These system control registers are protected after the power on reset till user to
disable register protection. For user to program these protected registers, a register protection disable
sequence needs to be followed by a special programming. The register protection disable sequence is
wri
ting the data “59h”, “16h” “88h” to the register REGWRPROT address at 0x5000_0100
continuously. Any different data value, different sequence or any other write to other address during
these three data writing will abort the whole sequence.
After the protection is disabled, user can check the protection disable bit at address 0x5000_0100 bit0,
1 is protection disable, and 0 is protection enable. Then user can update the target protected register
value and then write any data to the address “0x5000_0100” to enable register protection.
The protected registers are listed as following table.
Register
Bit
Description
IPRSTC1
[3] EBI_RST
EBI Controller Reset (Write-protection Bit)
IPRSTC1
[2] PDMA_RST
PDMA Controller Reset (Write Protect)
IPRSTC1
[1] CPU_RST
CPU Kernel One-Shot Reset (Write Protect)
IPRSTC1
[0] CHIP_RST
CHIP One-Shot Reset (Write Protect)
BODCR
[7] LVR_EN
Low Voltage Reset Enable Bit (Write Protect)
BODCR
[5] BOD_LPM
Brown-Out Detector Low Power Mode (Write Protect)
BODCR
[3] BOD_RSTEN
Brown-Out Reset Enable Bit (Write Protect)
BODCR
[2:1] BOD_VL
Brown-Out Detector Threshold Voltage Selection (Write Protect)
BODCR
[0] BOD_EN
Brown-Out Detector Enable Bit (Write Protect)
PORCR
[15:0] POR_DIS_CODE
Power-On-Reset Enable Bit (Write Protect)
REGWRPROT
[7:0] REGWRPROT
Register Write-Protection Code (Write Only)
REGWRPROT
[0] REGPROTDIS
Register Write-Protection Disable Index (Read Only)
NMI_SEL
[8] NMI_EN
NMI Interrupt Enable Bit (Write Protect)
PWRCON
[8] PD_WAIT_CPU
Power-Down Entry Condition Control (Write Protect)
PWRCON
[7] PWR_DOWN_EN
System Power-Down Enable Bit (Write Protect)
PWRCON
[5] PD_WU_INT_EN
Power-Down Mode Wake-Up Interrupt Enable Bit (Write Protect)