mc68hc05x4dw Freescale Semiconductor, Inc, mc68hc05x4dw Datasheet - Page 104

• Manufacturer Part Number: mc68hc05x4dw
• Description: Xc68hc705x4 Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

Core Timer
MC68HC05X4 Rev 1.0
8
8
Overflow
detect
circuit
CTOF RTIF CTOE RTIE
f
OP
To interrupt logic
Interrupt circuit
/ 2
10
flags, are located in the CTIMER control and status register (CTCSR) at
location $08.
CTOF (core timer overflow flag) is a read-only status bit which is set
when the 8-bit ripple counter rolls over from $FF to $00. A CPU interrupt
request will be generated if CTOE is set. Clearing CTOF is done by
writing a ‘0’ to it . Writing a ‘1’ to CTOF has no effect on the bit’s value.
Reset clears CTOF.
Freescale Semiconductor, Inc.
(Core timer control & status)
Figure 1. Core timer block diagram
For More Information On This Product,
(Core timer counter)
f
OP
$08 CTCSR
$09 CTCR
/ 2
Go to: www.freescale.com
17
0
RTI select circuit
Core Timer
Internal bus
0
RT1
7-bit counter
8
RT0
f
OP
/ 2
f
OP
14
/ 2
Internal processor clock
2
( 4 )
COP watchdog
f
OP
( 8 )
timer
reset
logic
To
COP
clear
2-ctimer