mc68hc11d0 Freescale Semiconductor, Inc, mc68hc11d0 Datasheet - Page 99

• Manufacturer Part Number: mc68hc11d0
• Description: Mc68hc11d0 Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

9.4.1 Timer Interrupt Mask 2 Register
TOI — Timer Overflow Interrupt Enable
RTII — Real-time Interrupt Enable
PAOVI — Pulse Accumulator Overflow Interrupt Enable
PAII — Pulse Accumulator Input Edge
9.4.1 Timer Interrupt Flag 2 Register
TECHNICAL DATA
TMSK2 — Timer Interrupt Mask 2
RESET:
The clock source for the RTI function is a free-running clock that cannot be stopped or
interrupted except by reset. This clock causes the time between successive RTI time-
outs to be a constant that is independent of the software latencies associated with flag
clearing and service. For this reason, an RTI period starts from the previous time-out,
not from when RTIF is cleared.
Every time-out causes the RTIF bit in TFLG2 to be set, and if RTII is set, an interrupt
request is generated. After reset, one entire real-time interrupt period elapses before
the RTIF flag is set for the first time. Refer to the TMSK2, TFLG2, and PACTL regis-
ters.
This register contains the real-time interrupt enable bits.
Refer to 9.6 Pulse Accumulator.
Refer to 9.6 Pulse Accumulator.
Bits of this register indicate the occurrence of timer system events. Coupled with the
four high-order bits of TMSK2, the bits of TFLG2 allow the timer subsystem to operate
in either a polled or interrupt driven system. Each bit of TFLG2 corresponds to a bit in
TMSK2 in the same position.
RTR[1:0]
Refer to 9.3 Output Compare.
0 = RTIF interrupts disabled
1 = Interrupt requested when RTIF is set to one
0 0
0 1
1 0
1 1
Bit 7
TOI
Bits in TMSK2 correspond bit for bit with flag bits in TFLG2. Ones in
TMSK2 enable the corresponding interrupt sources.
0
RTII
E = 1 MHz
10.923 ms
21.845 ms
Freescale Semiconductor, Inc.
2.731 ms
5.461 ms
6
0
For More Information On This Product,
PAOVI
Go to: www.freescale.com
5
0
TIMING SYSTEM
E = 2 MHz
16.384 ms
32.768 ms
4.096 ms
8.192 ms
PAII
4
0
NOTE
3
0
0
E = 3 MHz
16.384 ms
32.768 ms
65.536 ms
8.192 ms
2
0
0
PR1
1
0
E = X MHz
(E/2
(E/2
(E/2
(E/2
13
14
15
16
)
)
)
)
$0024
Bit 0
PR0
0
9-13