MC68HC05E0 Datasheet, PDF (63/96 Pages) Motorola, Inc – High-density complementary metal oxide semiconductor (HCMOS) microcontroller unit

The Timer A Prescaler register ($000A) is an 8-bit wide data register which is used for setting the
prescaler. It is a read/write register and can be loaded with any value between $00 and $FF.
Writing N to this register causes the prescaler to divide by N+1. Writing to this register resets the
entire timer.
With the bus clock running at 4 MHz, Timer A has a range of 16 µs to 32.8 ms.
7.3
Timer B
Timer B consists of a 14-bit free-running counter driving an 8-bit scaler (see Figure 7-3).
CETB
14 Bit
(freerunning)
INTMB
OF
8 Bit
7
INT1
(32 ms - 8 s)
Sub-system
Clock
Frequency
$000B
Timer B
Scaler Register
INTFB
Figure 7-3 Timer B Structure
The Timer B Scaler Register ($000B) is an 8-bit wide data register which is used for setting the
scaler. It is a read/write register and can be loaded with any value between $00 and $FF. Writing
N to this register causes the scaler to divide by N+1. Writing to this register resets the entire timer.
With the bus clock running at 4 MHz, this timer has a range of 32.8 ms to 8.4 s.
MC68HC05E0
TIMERS
MOTOROLA
7-3