AT89LP216_06 datasheet(28/90 Pages) ATMEL

28 / 90 page

3621A–MICRO–6/06

AT89LP216 [Preliminary]

Figure 14-1. Timer/Counter 1 Mode 0: Variable Width Counter

Mode 0 operation is the same for Timer 0 as for Timer 1, except that TR0, TF0 and INT0 replace

the corresponding Timer 1 signals in Figure 14-1. There are two different GATE bits, one for

Timer 1 (TMOD.7) and one for Timer 0 (TMOD.3). The INT0 and INT1 pins are shared with the

XTAL oscillator. They may only be used for the GATE function when using the internal RC oscil-

lator as the system clock.

14.2

Mode 1 – 16-bit Auto-Reload Timer/Counter

In Mode 1 the Timers are configured for 16-bit auto-reload. The Timer register is run with all

16 bits. The 16-bit reload value is stored in the high and low reload registers (RH1/RL1). The

clock is applied to the combined high and low timer registers (TH1/TL1). As clock pulses are

received, the timer counts up: 0000H, 0001H, 0002H, etc. An overflow occurs on the FFFFH-to-

0000H transition, upon which the timer register is reloaded with the value from RH1/RL1 and the

overflow flag bit in TCON is set. See Figure 14-2. The reload registers default to 0000H, which

gives the full 16-bit timer period compatible with the standard 8051. Mode 1 operation is the

same for Timer/Counter 0.

Figure 14-2. Timer/Counter 1 Mode 1: 16-bit Auto-Reload

OSC

T1 Pin

TR1

GATE

INT1 Pin

TL1

(8 Bits)

Control

Interrupt

C/T = 0

C/T = 1

PSC1

TH1

(8 Bits)

TF1

÷TPS

Mode 1:

Time-out Period

65536

RH0 RL0

}

–

()

Oscillator Frequency

----------------------------------------------------------

TPS 1

()

OSC

T1 Pin

TR1

GATE

INT1 Pin

TL1

(8 Bits)

Control

Interrupt

C/T = 0

C/T =1

TH1

(8 Bits)

TF1

RL1

(8 Bits)

RH1

(8 Bits)

Reload

÷TPS

AT89LP216 датащи(PDF) 28 Page - ATMEL Corporation

AT89LP216 датащи(HTML) 28 Page - ATMEL Corporation

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

датащи скачать

ссылки URL