Datasheet

DS_6612_001 78M6612 Data Sheet
Rev 2 23
3.5 Connecting LCDs
The 78M6612 has an on-chip LCD controller capable of controlling static or multiplexed LCDs. Figure 11
shows the basic connection for an LCD.
Figure 11: Connecting LCDs
The LCD segment pins can be organized in the following groups:
• Seventeen pins are dedicated LCD segment pins (SEG0 to SEG13, SEG16 to SEG18).
• Four pins are dual-function pins CKTEST/SEG19, E_RXTX/SEG38, E_TCLK/SEG33, and
E_RST/SEG32.
• Fourteen pins are available as combined DIO and segment pins SEG24/DIO4 to SEG31/DIO11,
SEG34/DIO14 to SEG37/DIO17, SEG39/DIO19, and SEG40/DIO20.
• The QFN-68 package adds an additional combination pin, SEG41/DIO21. Also adds two additional
LCD segment pins, SEG13 and SEG14.
3.6 Connecting I
2
C EEPROMs
I
2
C EEPROMs or other I
2
C compatible devices should be connected to the DIO pins DIO4 and DIO5, as
shown in Figure 12.
Pull-up resistors of roughly 10 kΩ to V3P3D should be used for both SCL and SDA signals. The
DIO_EEX register in I/O RAM must be set to 01 in order to convert the DIO pins DIO4 and DIO5 to I
2
C
pins SCL and SDA.
.
Figure 12: I
2
C EEPROM Connection
DIO4
DIO5
78M6612
EEPROM
SCL
SDA
V3P3D
10k
Ω
10k
Ω
DIO4
DIO5
EEPROM
SCL
SDA
V3P3D
10k
Ω
10k
Ω
segments
78M6612
LCD
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