68HC05CL48 datasheet(66/145 Pages) MOTOROLA

66 / 145 page

GENERAL RELEASE SPECIFICATION

June 11, 1997

MOTOROLA

TIMER

MC68HC05CL48

8-14

REV 2.0

The counter alternate register at address $1B and $1C contains the same value

as the free-running counter (at address $19 and $1A); therefore, this alternate

timer status register.

8.1.6 Timer Pin Conﬁguration Register (TIMCONF)

The timer pin conﬁguration register is a read/write register, this is used to control

PTC[6:7] pin function.

CONF7- Pin conﬁguration 7

1 =

Conﬁgures PTC7 as timer input capture pin.

0 =

PTC7 used as normal I/O port pin.

CONF6- Pin conﬁguration 6

1 =

Conﬁgures PTC6 as timer input capture pin.

0 =

PTC6 used as normal I/O port pin.

8.1.7 Operation During Low Power Mode

During the wait and stop modes, the timer stops and holds at its current state,

retaining all data, and resumes operation from this point when external interrupt

(IRQ), or internal interrupt is received.

8.2

CORE TIMER

The MC68HC05CL48 Core Timer (or Ctimer) for is a 15-stage multi-functional

ripple counter. The features include Timer Over Flow, Power-On Reset (POR),

Real Time Interrupt, and COP Watchdog Timer.

As seen in Figure 8-6, the Timer is driven by the internal bus clock divided by four

with a ﬁxed prescaler. This signal drives an 8-bit ripple counter. The value of this

8-bit ripple counter can be read by the CPU at any time by accessing the Ctimer

Counter Register (CTCR) at address $09. A timer overﬂow function is

implemented on the last stage of this counter, giving a possible interrupt at the

rate of E/1024. One additional stages produce the POR function at E/2064. The

Timer Counter Bypass circuitry (available only in Test Mode) is at this point in the

76543210

TIMCONF

$0006

READ

CONF7

CONF6

WRITE

RESET

UUUUU

U = UNAFFECTED

68HC05CL48 Datasheet(PDF) 66 Page - Motorola, Inc

68HC05CL48 Datasheet(HTML) 66 Page - Motorola, Inc

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL