mc68hc705j2 Freescale Semiconductor, Inc, mc68hc705j2 Datasheet - Page 60

• Manufacturer Part Number: mc68hc705j2
• Description: 8-bit Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

7.1 Timer Counter Register (TCR)
TCR — Timer Counter Register
RESET
7.2
TCSR — Timer Control and Status Register
RESET
MOTOROLA
7-2
Timer Control and Status Register (TCSR)
A 15-stage ripple counter is the core of the timer. The value of the first eight
stages is readable at any time from the read-only timer counter register shown
in Figure 7-2.
Power-on clears the entire counter chain and begins clocking the counter. After
4064 cycles of the internal clock, the power-on reset circuit is released, clearing
the counter again and allowing the MCU to come out of reset.
A timer overflow function at the eighth counter stage makes timer interrupts
possible every 1024 internal clock cycles.
Timer interrupt flags, timer interrupt enable bits, and real-time interrupt rate
select bits are in the read/write timer control and status register.
Bit 7
Bit 7
TOF
Figure 7-3. Timer Control and Status Register (TCSR)
0
0
Figure 7-2. Timer Counter Register (TCR)
RTIF
6
0
6
0
TOIE
5
0
5
0
RTIE
4
0
4
0
TIMER
3
0
3
0
0
2
0
2
0
0
RT1
1
0
1
1
MC68HC705J2
Bit 0
Bit 0
RT0
0
1
$ 0 0 0 9
$ 0 0 0 8