W742C813 Datasheet, PDF (44/56 Pages) Winbond – 4 BIT MICROCONTROLLER

W742E/C813
5.25.3 SEG32-SEG39 Using as DC Output (NMOS open drain type)
SEG32−SEG39 pins output type can be changed to DC output mode by code mask option. The
correspoinding control resigters are LCD RAM address LCDR40 and LCDR41, these two parts are
individually enabled by code mask option. LCDR40 controls the SEG32−SEG35 pins and LCDR41
controls the SEG36−SEG39 pins. When SEG32−SEG39 are used as DC output, their output type is
NMOS open drain type. The instruction MOV @LP,R outputs the ram data to SEG32−39, when
SEG32−39 operate in DC output mode.
5.25.4 The Output Waveforms for the LCD Driving Mode
1/5 bias 1/8 (1/16) duty Lighting System (Example)
Normal Operating Mode
COM0
1
2
3
4
"
"
"
8
(16)
1
2
3
4
"
"
"
8
(16)
"""
"""
VLCD
V1
V2
V3
V4
VSS
SEG
"""
"""
VLCD
V1
V2
V3
V4
VSS
LCD driver
outputs for
seg. on
COM0 side
being lit
"""
"""
VLCD
V1
V2
V3
V4
VSS
-V1
-V2
-V3
-V4
-VLCD
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