Intel PXA255 Personal Computer User Manual


 
Intel® PXA255 Processor Developer’s Manual 3-33
Clocks and Power Manager
3.5.11 Reset Controller Status Register (RCSR)
The CPU uses the RCSR, shown in Table 3-19, to determine a reset’s last cause or causes. The
processor can be reset in four ways:
Hardware reset
Watchdog reset
Sleep mode
GPIO reset
Refer to Table 2-4, “Effect of Each Type of Reset on Internal Register State” on page 2-6 for details
of the behavior of different modules during each type of reset.
Each RCSR status bit is set by a different reset source and can be cleared by writing a 1 back to the
bit. The RCSR status bits for watchdog reset, sleep mode, and GPIO resets have a hardware reset
state of zero.
This is a read/write register. Ignore reads from reserved bits. Write zeros to reserved bits.
Table 3-18. PGSR2 Bit Definitions
0x40F0_0028 PGSR2 Clocks and Power Manager
Bit
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
reserved
SS84
SS83
SS82
SS81
SS80
SS79
SS78
SS77
SS76
SS75
SS74
SS73
SS72
SS71
SS70
SS69
SS68
SS67
SS66
SS65
SS64
Reset 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Bits Name Description
[31:17] reserved
[16:0] SSx
If programmed as an output, Sleep state of GPx
0 – Pin is driven to a zero during sleep mode
1 – Pin is driven to a one during sleep mode
Cleared by hardware, watchdog, and GPIO resets.