SYS_NVFLAGS Register
The SYS_NVFLAGS Register is one of the two flag registers. It contains the current states of
the flags.
The SYS_NVFLAGS Register is non
‑
volatile, that is, a reset signal from the reset push button
does not reset the SYS_FLAGS Register. Only
CB_nPOR
resets the SYS_NVFLAGS Register.
You use the SYS_NVFLAGSSET Register to set bits in the SYS_NVFLAGS Register. Write
0b1
to set the associated flag. Write
0b0
to leave the associated flag unchanged.
You use the SYS_NVFLAGSCLR Register to clear bits in the SYS_NVFLAGS Register. Write
0b1
to clear the associated flag. Write
0b0
to leave the associated flag unchanged.
4.6.7
SYS_CFGSW Register
The SYS_CFGSW Register characteristics are:
Purpose
Contains the value of
CONFSWITCH
in the
config.txt
file.
Usage constraints
There are no usage constraints.
Configurations
Available in all N1 board configurations.
Memory offset and full register reset value
See
4.6.1 APB system register summary
The following table shows the bit assignments.
Table 4-130 SYS_CFGSW Register bit assignments
Bits
Name
Type
Function
[31:8]
-
-
Reserved.
[7:0]
SOFT_CONFIG_SWITCH
RW
Software applications can read these switch
settings. The application software defines the
meanings of the switch settings. The reset
signals set these bits to the value of
CONFSWITCH
in the
config.txt
file.
Note
The configuration system does not use the
contents of this register for board
configuration.
4.6.8
SYS_24MHZ Register
The SYS_24MHZ Register characteristics are:
Purpose
A 32
‑
bit counter that updates at 24MHz. The clock source is the 24MHz clock generator on the
N1 SDP.
Usage constraints
This register is read
‑
only.
4 Programmers model
4.6 APB system registers
101489_0000_02_en
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