HT56RB688 datasheet(52/164 Pages) HOLTEK

52 / 164 page

Timer Control Registers - TMR0C, TMR1C, TMR2C, TMR3C

The flexible features of the Holtek microcontroller Timer/Event Counters enable them to operate in

three different modes, the options of which are determined by the contents of their respective control

It is the Timer Control Register together with its corresponding timer registers that control the full

operation of the Timer/Event Counters. Before the timers can be used, it is essential that the

appropriate Timer Control Register is fully programmed with the right data to ensure its correct

operation, a process that is normally carried out during program initialisation.

To choose which of the three modes the timer is to operate in, either in the timer mode, the event

counting mode or the pulse width measurement mode, bits 7 and 6 of the corresponding Timer Control

timer-on bit, which is bit 4 of the Timer Control Register and known as TnON, depending upon which

timer is used, provides the basic on/off control of the respective timer. Setting the bit high allows the

counter to run, clearing the bit stops the counter. For timers that have prescalers, bits 0~2 of the Timer

Control Register determine the division ratio of the input clock prescaler. The prescaler bit settings

have no effect if an external clock source is used. If the timer is in the event count or pulse width

measurement mode, the active transition edge level type is selected by the logic level of bit 3 of the

Timer Control Register which is known as TnE. An additional TnS bit in the 16-bit Timer/Event

Counter control register is used to determine the clock source for the Timer/Event Counter.

Timer/Event Counter Control Register - TMRnC (n=0, 2, 3)

Bit

76543210

Name

TnM1

TnM0

TnON

TnE

TnPSC2

TnPSC1

TnPSC0

R/W

POR

01000

Bit 7~6

TnM1~TnM0: Timer/Event Counter Operating mode selection bit

00: no mode available

01: Event Counter mode

10: Timer mode

11: Pulse width measurement mode

Bit 5

Unimplemented, read as

²0²

Bit 4

TnON: Timer/Event Counter counting enable control

0: disable

1: enable

Bit 3

TnE: Timer/Event Counter active edge selection bits

For Event counter mode:

0: count on rising edge

1: count on falling edge

For Pulse width measurement mode:

0: start counting on falling edge

1: start counting on rising edge

Bit 2~0

TnPSC2~TnPSC0: Timer/Event Counter prescaler rate selection bits

000: 1/1

001: 1/2

010: 1/4

011: 1/8

100: 1/16

101: 1/32

110: 1/64

111: 1/128

Rev. 1.00

December 2, 2011

HT56RB688

TinyPowerTM A/D type Smart Card OTP MCU

with LCD, DAC, ISO 7816 and USB Interfaces

HT56RB688 Datasheet(PDF) 52 Page - Holtek Semiconductor Inc

HT56RB688 Datasheet(HTML) 52 Page - Holtek 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