MC9S08AW60 FREESCALE [Freescale Semiconductor, Inc], MC9S08AW60 Datasheet - Page 78

• Manufacturer Part Number: MC9S08AW60
• Description: Microcontrollers
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

Chapter 5 Resets, Interrupts, and System Configuration
5.9.7
This register contains one read-only status flag, one write-only acknowledge bit, three read/write delay
selects, and three unimplemented bits, which always read 0.
1
78
RTICLKS
RTIS[2:0]
Normal values are shown in this column based on f
Specifications,” f
Reset
RTIACK
RTIS2:RTIS1:RTIS0
Field
RTIE
RTIF
2:0
7
6
5
4
W
R
0:0:0
0:0:1
0:1:0
0:1:1
1:0:0
1:0:1
1:1:0
1:1:1
System Real-Time Interrupt Status and Control Register (SRTISC)
RTIF
Real-Time Interrupt Flag — This read-only status bit indicates the periodic wakeup timer has timed out.
0 Periodic wakeup timer not timed out.
1 Periodic wakeup timer timed out.
Real-Time Interrupt Acknowledge — This write-only bit is used to acknowledge real-time interrupt request
(write 1 to clear RTIF). Writing 0 has no meaning or effect. Reads always return logic 0.
Real-Time Interrupt Clock Select — This read/write bit selects the clock source for the real-time interrupt.
0 Real-time interrupt request clock source is internal 1-kHz oscillator.
1 Real-time interrupt request clock source is external clock.
Real-Time Interrupt Enable — This read-write bit enables real-time interrupts.
0 Real-time interrupts disabled.
1 Real-time interrupts enabled.
Real-Time Interrupt Delay Selects — These read/write bits select the wakeup delay for the RTI. The clock
source for the real-time interrupt is a self-clocked source which oscillates at about 1 kHz, is independent of other
MCU clock sources. Using external clock source the delays will be crystal frequency divided by value in
RTIS2:RTIS1:RTIS0. See
0
7
RTI
for the tolerance on these values.
= Unimplemented or Reserved
Figure 5-9. System RTI Status and Control Register (SRTISC)
RTIACK
0
0
6
Table 5-9. SRTISC Register Field Descriptions
Disable periodic wakeup timer
1-kHz Clock Source Delay
Table 5-10. Real-Time Interrupt Frequency
Table
RTICLKS
0
5
MC9S08AW60 Data Sheet, Rev 2
5-10.
128 ms
256 ms
512 ms
1.024 s
32 ms
64 ms
8 ms
RTI
= 1 kHz. See
RTIE
0
4
Description
1
Appendix A, “Electrical Characteristics and Timing
3
0
0
Using External Clock Source Delay
Disable periodic wakeup timer
RTIS2
0
2
(Crystal Frequency)
divide by 16384
divide by 32768
divide by 2048
divide by 4096
divide by 8192
divide by 1024
divide by 256
Freescale Semiconductor
RTIS1
0
1
RTIS0
0
0