AP160 AMICC [AMIC Technology], AP160 Datasheet - Page 11

• Manufacturer Part Number: AP160
• Description: 8-BIT MICROCONTROLLER WITH 8KB OTP
• Manufacturer: AMICC [AMIC Technology]

AP160
Programmable Clock Out
A 50% duty cycle clock can be programmed to come out on P1.0, as shown in Figure 5. This pin, besides being a regular
I/O pin, has two alternate functions. It can be programmed to input the external clock for Timer/Counter 2 or to output a 50%
duty cycle clock ranging from 61 HZ to 4MHZ at a 16MHZ operating frequency. To configure the Timer/Counter 2 as a clock
generator, bit C/T2 (T2CON.1) must be cleared and bit T2OE (T2MOD.1) must be set. Bit Tr2 (T2CON.2) starts and stops
the timer. The clock-out frequency depends on the oscillator frequency and the reload value of Timer 2 capture registers
(RCAP2H, RCAP2L), as shown in the following equation.
Oscillator
Frequency
Clock
Out
Frequency
4
[
65535
(
RCAP
2
H
,
RCAP
2
L
)]
In the clock-out mode, Timer 2 roll-overs will not generate an interrupt. This behavior is similar to when Timer 2 is used as a
baud-rate generator. It is possible to use Timer 2 as a baud-rate generator and a clock generator simultaneously. Note,
however, that the baud-rate and clock-out frequencies cannot be determined independently from one another since they
both use RCAP2H and RCAP2L.
TL2
TH2
OSC
2
(8 BITS)
(8 BITS)
TR2
RCAP2L
RCAP2H
C/T2 BIT
P1.0
2
(T2)
T2OE (T2MOD.1)
TRANSITION
DETECTOR
TIMER 2
P1.1
EXF2
INTERRUPT
(T2EX)
EXEN2
Figure 5. Timer 2 in Clock-Out Mode
AMIC Technology, Inc.
Version 0.0
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