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Programmers Model
ARM DUI 0447J
Copyright © 2009-2014, ARM. All rights reserved.
4-12
ID052914
Non-Confidential
Figure 4-5
shows the bit assignments.
Figure 4-5 SYS_LED Register bit assignments
Table 4-6
shows the bit assignments.
4.4.4
100Hz Counter Register
The SYS_100HZ Register characteristics are:
Purpose
A 32-bit counter incremented at 100Hz. The 100Hz reference is derived
from the on-board 32.768kHz crystal oscillator. The register is set to zero
by a
CB_nRST
reset, and when read, returns the count since the last reset.
Usage constraints
There are no usage constraints.
Configurations
Available in all configurations.
Attributes
See
Table 4-3 on page 4-8
.
Table 4-7
shows the bit assignments.
4.4.5
Flag Registers
The SYS_* Registers characteristics are:
Purpose
Provides two 32-bit register locations containing general-purpose flags.
You can assign any meaning to the flags.
Usage constraints
There are no usage constraints.
Configurations
Available in all configurations.
Attributes
See
Table 4-3 on page 4-8
.
31
8 7
0
Undefined
LED[7:0]
Table 4-6 SYS_LED Register bit assignments
Bits
Access
Name
Reset
Description
[31:8]
Read-only
-
-
Reserved
[7:0]
Read-write
LED[7:0]
0xXX
Set the corresponding register bit to 1 to light the LED.
Table 4-7 SYS_100HZ Register bit assignments
Bits
Name
Reset
Description
[31:0]
SYS_100HZ
0xXXXXXXXX
100Hz counter