MC9S08JM16 Datasheet, PDF (72/386 Pages) Freescale Semiconductor, Inc – Microcontrollers

Chapter 5 Resets, Interrupts, and System Configuration
Table 5-6. COP Configuration Options
Control Bits
COPCLKS
COPT[1:0]
Clock Source
COP Window¹ Opens
(COPW = 1)
COP Overflow Count
N/A
0:0
N/A
N/A
COP is disabled
0
0:1
1 kHz LPO
clock
N/A
2⁵ cycles (32 ms²)
0
1:0
1 kHz LPO
clock
N/A
2⁸ cycles (256 ms¹)
0
1:1
1 kHz LPO
clock
N/A
2¹⁰ cycles (1.024 s¹)
1
0:1
BUSCLK
6144 cycles
2¹³ cycles
1
1:0
BUSCLK
49,152 cycles
2¹⁶ cycles
1
1:1
BUSCLK
196,608 cycles
2¹⁸ cycles
1 _{Windowed COP operation requires the user to clear the COP timer in the last 25% of the selected timeout period. This column}
displays the minimum number of clock counts required before the COP timer can be reset in windowed COP mode (COPW = 1).
2 _{Values shown in milliseconds based on tLPO = 1 ms. See tLPO in the appendix Section A.12.1, “Control Timing,” for the}
tolerance of this value.
5.7.5 System Options Register 2 (SOPT2)
7
6
5
4
3
2
R
0
0
0
COPCLKS¹ COPW¹
SPI1FE
W
Reset
0
0
0
0
0
1
= Unimplemented or Reserved
1 _{This bit can be written only one time after reset. Additional writes are ignored.}
Figure 5-6. System Options Register 2 (SOPT2)
1
SPI2FE
1
0
ACIC
0
Table 5-7. SOPT2 Register Field Descriptions
Field
Description
7
COP Watchdog Clock Select — This write-once bit selects the clock source of the COP watchdog.
COPCLKS 0 Internal 1 KHz LPO clock is source to COP.
1 Bus clock is source to COP.
6
COPW
COP Window — This write-once bit selects the COP operation mode. When set, the 0x55-0xAA write sequence
to the SRS register must occur in the last 25% of the selected period. Any write to the SRS register during the
first 75% of the selected period will reset the MCU.
0 Normal COP operation.
1 Window COP operation.
2
SPI1FE
SPI1 Ports Input Filter Enable
0 Disable input filter on SPI1 port pins to allow for higher maximum SPI baud rate.
1 Enable input filter on SPI1 port pins to eliminate noise and restrict maximum SPI baud rate.
MC9S08JM16 Series Data Sheet, Rev. 2
72
Freescale Semiconductor