W925EP01 Datasheet, PDF (51/108 Pages) Winbond – 8-BIT CID MICROCONTROLLER

W925EP01/ W925EP01FG
MODE 2
Mode 2 is the Auto Reload Mode. In mode 2, TLx acts as an 8-bit count register, while THx holds the
reload value. When the TLx register overflows from FFh to 00h, the TFx bit is set and TLx is reloaded
with the content of THx, and the counting process continues from the reloaded TLx. The reload
operation leaves the content of the THx register unchanged. The TRx bit and the proper setting of
GATE and INTx pins controll counting.
BUZZER
In mode 2, timer 0 can be use to output an arbitrary frequency to the BUZ pin by programming bit6
and bit7 of CKCON2. BUZ pin can be configured as key tone (KT) output by set BUZSL to high. When
disable buzzer output by clearing ENBUZ to low, the BUZ output is in floating status.
In the case where timer 0 clock input is FT, the desired frequency for BUZ output = FT / (255 – preset
value + 1) / 2 (HZ).
CKCON2.5, CKCON2.4
Low
TM0=CKCON1.2, CKCON1.3
(TM1=CKCON1.4, CKCON1.5)
512Hz
1024Hz
Fosc/4 ⁰⁰
Fosc/64 ⁰¹
Fosc/1024 ^{10 mux}
Fs ¹¹
T0 = P3.4
2048Hz
C/T = TMOD.2
(C/T = TMOD.6)
0 _FT
1
0
(T1 = P3.5)
TR0 = TCON.4
(TR1 = TCON.6)
00
01
10 mux
11
TL0
From
TM0
(TL1)
CKCON2.6 CKCON2.7
=BUZSL =ENBUZ
KT
1/2
Pin BUZ
floating
7
TFx
Interrupt
TF0
(TF1)
GATE = TMOD.3
(GATE = TMOD.7)
INT0 = P3.2
(INT1 = P3.3)
0
7
TH0
(TH1)
PS: Functions of timer1 are shown in brackets
Figure 6-6 Mode 2 of Timer/Counter 0 & 1
When FT equals 32768 Hz, depending on the preset value of TM0, the BUZ pin will output a single
tone signal in the tone frequency range from 64 Hz to 16384 Hz. The relation between the tone
frequency and the preset value of TM0 is shown in the table below.
- 51 -
Publication Release Date: Apr. 10, 2006
Revision A2