W742C814 データシートの表示（PDF） - Winbond

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W742C814

4-BIT MICROCONTROLLER

Winbond 

W742C814

0, and the specified value can be loaded into TM0. Then we can set MR0.3 to 1, that will cause the

event flag 1 (EVF.1) is reset and the TM0 starts to count. When it decreases and underflow to FFH,

Timer 0 stops operating and generates an underflow (EVF.1 = 1). Then, if the Timer 0 interrupt enable

flag has been set (IEF.1 = 1), the interrupt is executed, while if the hold release enable flag 1 has

been set (HEF.1 = 1), the hold state is terminated. The Timer 0 clock input can be set as FOSC/1024

or FOSC/4 by setting MR0.0 to 1 or resetting MR0.0 to 0. The default timer value is FOSC/4. The

organization of Timer 0 is shown in Figure 6-6.

If the Timer 0 clock input is FOSC/4:

Desired Timer 0 interval = (preset value +1) × 4 × 1/FOSC

If the Timer 0 clock input is FOSC/1024:

Desired Timer 0 interval = (preset value +1) × 1024 × 1/FOSC

Preset value: Decimal number of Timer 0 preset value

FOSC: Clock oscillation frequency

Fosc/1024

Fosc/4

1. Reset

2. CLR EVF,#02H

3. Reset MR0.3 to 0

4.MOV TM0L,R or MOV TM0H,R

MR0.0

Disable

Enable

Set MR0.3 to 1

8-Bit Binary

Down Counter

(Timer 0)

4

4

MOV TM0H,R MOV TM0L,R

SQ

R

EVF.1

HEF.1

IEF.1

Hold mode release (HCF.1)

Timer 0 interrupt (INT1)

1. Reset

2. CLR EVF,#02H

3.Set MR0.3 to 1

Figure 6-6 Organization of Timer 0

6.11.2 Timer 1 (TM1)

Timer 1 (TM1) is also a programmable 8-bit binary down counter, as shown in Figure 6-7. Timer 1 can

be used as to output an arbitrary frequency to the MFP pin. The input clock of Timer 1 can be one of

three sources: FOSC/64, FOSC, or Fslow. The source can be selected by setting bit 0 and bit 1 of mode

register 1 (MR1). At initial reset, the Timer 1 clock input is FOSC. When the MOV TM1L, R or MOV

TM1H,R instruction is executed, the specified data are loaded into the auto-reload buffer; but the TM1

down-counting will keep going on. If the bit 3 of MR1 is set (MR1.3 = 1), the content of the auto-reload

buffer will be loaded into the TM1 down counter, and Timer 1 starts to down count, and the event flag

7 is reset (EVF.7=0). When the timer decreases and underflow to FFH, it will generate an underflow

(EVF.7 = 1) and be auto-reloaded with the specified data, after which it will continue to count down.

Then, if interrupt enable flag 7 has been set to 1 (IEF.7 = 1), an interrupt is executed; if hold mode

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