PXR40RM Datasheet, PDF (504/1434 Pages) Freescale Semiconductor, Inc – PXR40 Microcontroller

Software Watchdog Timer (SWT)
18.3.2.7 SWT Service Key Register (SWT_SK)
The SWT Service Key (SWT_SK) register holds the previous (or initial) service key value. This register
is read only if either the SWT_MCR[HLK] or SWT_MCR[SLK] bits are set.
Offset 0x018
Access: Read/Write
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
R0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
SK¹
W
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
NOTES:
1 _{If neither HLK or SLK lock bit in the SWT_MCR is set, the SWT_SK can be initialized by software to a non-zero}
value.
Figure 18-7. SWT Service Key Register (SWT_SK)
Table 18-8. SWT_SK Field Descriptions
Field
Description
0–15 Reserved
16–31 Service Key. This field is the previous (or initial) service key value used in keyed service mode. If
SK SWT_MCR[KEY] is set, the next key value to be written to the SWT_SR is (17*SK+3) mod 2¹⁶.
18-8
PXR40 Microcontroller Reference Manual, Rev. 1
Freescale Semiconductor