EM78808
8-bit Micro-controller
frame
V1
v2
v3
v4
v5
Gnd
com0
V1
v2
v3
v4
v5
Gnd
com1
com2
V1
v2
v3
v4
v5
Gnd
V1
v2
v3
seg
seg
v4
v5
Gnd
dark
V1
v2
v3
v4
v5
Gnd
light
Fig.19b LCD waveform (1/5 bias) for 1/24 duty
Bit 4(CDAS) : Current DA switch
0 ꢂnormal PORT66
1 ꢂCurrent DA output
Bit 5(KTS) : Key tone output switch
0 ꢂnormal PORT67
1 ꢂkey tone output .
Bit 6~Bit 7(KT0~KT1) : Key tone output frequency and its power control
KT1
KT0
Key tone frequency and power
0
0
1
1
0
1
0
1
32.768KHz/32 = 1.024kHz clock and enable
32.768KHz/16 = 2.048kHz clock and enable
32.768KHz/8 = 4.096kHz clock and enable
Power off key tone
______________________________________________________________________________________________________________________________________________________
* This specification is subject to change without notice.
8/1/2004 (V3.1)
33
ELAN [ ELAN MICROELECTRONICS CORP ]
