MC908QT4MPE datasheet(127/184 Pages) FREESCALE

127 / 184 page

Input/Output Registers

MC68HC908QY/QT Family Data Sheet, Rev. 5

Freescale Semiconductor

127

14.9.1 TIM Status and Control Register

The TIM status and control register (TSC) does the following:

•

Enables TIM overflow interrupts

•

Flags TIM overflows

•

Stops the TIM counter

•

Resets the TIM counter

•

Prescales the TIM counter clock

TOF — TIM Overflow Flag Bit

This read/write flag is set when the TIM counter reaches the modulo value programmed in the TIM

counter modulo registers. Clear TOF by reading the TIM status and control register when TOF is set

and then writing a 0 to TOF. If another TIM overflow occurs before the clearing sequence is complete,

then writing 0 to TOF has no effect. Therefore, a TOF interrupt request cannot be lost due to

inadvertent clearing of TOF. Reset clears the TOF bit. Writing a 1 to TOF has no effect.

1 = TIM counter has reached modulo value

0 = TIM counter has not reached modulo value

TOIE — TIM Overflow Interrupt Enable Bit

This read/write bit enables TIM overflow interrupts when the TOF bit becomes set. Reset clears the

TOIE bit.

1 = TIM overflow interrupts enabled

0 = TIM overflow interrupts disabled

TSTOP — TIM Stop Bit

This read/write bit stops the TIM counter. Counting resumes when TSTOP is cleared. Reset sets the

TSTOP bit, stopping the TIM counter until software clears the TSTOP bit.

1 = TIM counter stopped

0 = TIM counter active

NOTE

Do not set the TSTOP bit before entering wait mode if the TIM is required

to exit wait mode. When the TSTOP bit is set and the timer is configured for

input capture operation, input captures are inhibited until the TSTOP bit is

cleared.

When using TSTOP to stop the timer counter, see if any timer flags are set.

If a timer flag is set, it must be cleared by clearing TSTOP, then clearing the

flag, then setting TSTOP again.

Address: $0020

Bit 7

654321

Bit 0

Read:

TOF

TOIE

TSTOP

PS2

PS1

PS0

Write:

TRST

Reset:

00100000

= Unimplemented

Figure 14-4. TIM Status and Control Register (TSC)

MC908QT4MPE Datasheet(PDF) 127 Page - Freescale Semiconductor, Inc

MC908QT4MPE Datasheet(HTML) 127 Page - Freescale Semiconductor, 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