System Protection Control Register (Sypcr) - Motorola MPC8260 PowerQUICC II User Manual

Part II. ConÞguration and Reset

4.3.2.8 System Protection Control Register (SYPCR)

The system protection control register, shown in Figure 4-30, controls the system monitors,
software watchdog period, and bus monitor timing. SYPCR can be read at any time but can
be written only once after system reset.
Bits 0 1 2
Field
Reset
R/W
Addr
Bits 16 17 18
Field
Reset
R/W
Addr
Figure 4-30. System Protection Control Register (SYPCCR)
Table 4-14 describes SYPCR Þelds.
Bits Name
0Ð15 SWTC Software watchdog timer count. Contains the count value for the software watchdog timer.
16Ð23 BMT Bus monitor timing. DeÞnes the time-out period for the bus monitor, the granularity of this Þeld is 8
bus clocks. (BMT = 0xFF is translated to 0x7f8 clock cycles). BMT is used both in the 60x and local
bus monitors.
Note that the value 0 in invalid; an error is generated for each bus transaction.
24 PBME 60x bus monitor enable.
0 60x bus monitor is disabled.
1 The 60x bus monitor is enabled.
25 LBME Local bus monitor enable.
0 Local bus monitor is disabled.
1 The local bus monitor is enabled.
26Ð29 Ñ Reserved, should be cleared.
29 SWE Software watchdog enable. Enables the operation of the software watchdog timer. It should be
cleared by software after a system reset to disable the software watchdog timer.
30 SWRI Software watchdog reset/interrupt select.
0 Software watchdog timer and bus monitor time-out causes a machine check interrupt to the core.
1 Software watchdog timer and bus monitor time-out causes a soft reset (this is the default value
after soft reset).
31 SWP Software watchdog prescale. Controls the divide-by-2,048 software watchdog timer prescaler.
0 The software watchdog timer is not prescaled.
1 The software watchdog timer clock is prescaled.
4-35
3 4 5 6
1111_1111_1111_1111
19 20 21 22
BMT
1111_1111
Table 4-14. SYPCR Field Descriptions
MPC8260 PowerQUICC II UserÕs Manual
7 8 9 10
SWTC
R/W
0x10004
23 24 25 26
PBME LBME
0 0
R/W
0x10006
Description
11 12 13 14
27 28 29 30
Ñ SWE SWRI SWP
00_0 1 1
MOTOROLA
15
31
1