MC68HC11A1 MOTOROLA [Motorola, Inc], MC68HC11A1 Datasheet - Page 32

• Manufacturer Part Number: MC68HC11A1
• Description: 8-Bit Microcontrollers
• Manufacturer: MOTOROLA [Motorola, Inc]

8 Main Timer
32
MOTOROLA
The main timer is based on a free-running 16-bit counter with a four-stage programmable prescaler. A
timer overflow function allows software to extend the system's timing capability beyond the counter's
16-bit range.
The timer has three channels of input capture and five channels of output compare.
Refer to the following table for a summary of crystal-related frequencies and periods.
overflow —
overflow —
overflow —
overflow —
1 count —
1 count —
1 count —
1 count —
RTR[1:0]
Control
PR[1:0]
Bits
0 0
0 1
1 0
1 1
0 0
0 1
1 0
1 1
65.536 ms
262.14 ms
524.29 ms
16.384 ms
32.768 ms
65.536 ms
8.192 ms
4.0 MHz
1.0 MHz
1000 ns
16.0 s
1.049 s
1.0 s
4.0 s
8.0 s
Table 6 Timer Summary
32.768 ms
131.07 ms
262.14 ms
524.29 ms
16.384 ms
32.768 ms
Periodic (RTI) Interrupt Rates
4.096 ms
8.192 ms
8.0 MHz
2.0 MHz
500 ns
500 ns
2.0 s
4.0 s
8.0 s
Main Timer Count Rates
XTAL Frequencies
21.845 ms
87.381 ms
174.76 ms
349.52 ms
10.923 ms
21.845 ms
12.0 MHz
2.731 ms
5.461 ms
1.333 s
2.667 s
5.333 s
3.0 MHz
333 ns
333 ns
MC68HC11A8TS/D
Other Rates
(E/2
(E/2
(E/2
(E/2
(E/2
(E/2
(E/2
(E/2
(E/16)
(1/E)
(E/1)
(E/4)
(E/8)
(E)
MC68HC11A8
16
18
19
20
13
14
15
16
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