MC68HC711KS2MFN4 Freescale Semiconductor, MC68HC711KS2MFN4 Datasheet - Page 185

• Manufacturer Part Number: MC68HC711KS2MFN4
• Description: 32K EPROM - SLOW MODE
• Manufacturer: Freescale Semiconductor

9.4 Input Capture and Output Compare Overview
M68HC11K Family
MOTOROLA
The free-running counter begins incrementing from $0000 as the MCU
comes out of reset and continues to the maximum count, $FFFF. At the
maximum count, the counter rolls over to $0000, sets the timer overflow
flag (TOF) in the timer interrupt flag 2 (TFLG2) register, and continues to
increment. The value in this counter can be read in the timer counter
(TCNT) register, but cannot be written or changed except by reset.
The pulse accumulator, described in
derives its clock by post-scaling the main timer so that the output
frequency is always E clock divided by 64. This clock drives an 8-bit
counter while the pulse accumulator is operating in event counting
mode.
RTI is a programmable periodic interrupt circuit that can be used to pace
the execution of software routines, as described in
Interrupt
clock driving the free-running counter. The post-scaler output of this
chain runs at a frequency of E clock divided by 2
The COP watchdog timer
System) further divides the RTI clock by four to drive its circuitry at a
frequency of E clock divided by 2
The M68HC11K series features:
Each of the three input capture functions has its own 16-bit input capture
register (time capture latch) and each of the output compare functions
has its own 16-bit compare register. All timer functions, including the
timer overflow and RTI, have their own interrupt controls and separate
interrupt vectors.
•
•
•
Three input capture channels
Four output compare channels
One channel that can be selected to perform either input capture
or output compare
(RTI). The clock driving this function is also derived from the
Timing System
(5.3.3 Computer Operating Properly (COP)
15
Input Capture and Output Compare Overview
.
9.7 Pulse Accumulator
13
.
9.8 Real-Time
Timing System
Technical Data
(PA),
185