4.3.7. Flag Registers, SYS_FLAGSx and SYS_NVFLAGSx

The registers listed in Table 4.10 (SYS_FLAGS and SYS_NVFLAGS) provide two 32-bit register locations containing general-purpose flags. You can assign any meaning to the flags.

Table 4.10. Flag registers

Register

Address

Access

Reset by

Description

SYS_FLAGS0x10000030ReadResetFlag register
SYS_FLAGSSET0x10000030WriteResetFlag Set register
SYS_FLAGSCLR0x10000034WriteResetFlag Clear register
SYS_NVFLAGS0x10000038ReadPORNonvolatile Flag register
SYS_NVFLAGSSET0x10000038WritePORNonvolatile Flag Set register
SYS_NVFLAGSCLR0x1000003CWritePORNonvolatile Flag Clear register

The board provides two distinct types of flag register:

Flag and Nonvolatile Flag Registers

The SYS_FLAGS and SYS_NVFLAGS registers contain the current state of the flags.

Flag and Nonvolatile Flag Set Registers

The SYS_FLAGSSET and SYS_NVFLAGSSET registers are used to set bits in the SYS_FLAGS and SYS_NVFLAGS registers:

  • write 1 to SET the associated flag

  • write 0 to leave the associated flag unchanged.

Flag and Nonvolatile Flag Clear Registers

The SYS_FLAGSCLR and SYS_NVFLAGSCLR registers are used to clear bits in the SYS_FLAGS and SYS_NVFLAGS registers:

  • write 1 to CLEAR the associated flag

  • write 0 to leave the associated flag unchanged.

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