78M6612 Data Sheet
DS_6612_001
V3P3D
10kΩ
10kΩ
78M6612
EEPROM
DIO4
DIO5
SCL
SDA
.
Figure 32: I2C EEPROM Connection
3.8 Connecting 3-Wire EEPROMs
µWire EEPROMs and other compatible devices should be connected to the DIO pins DIO4 and DIO5, as
shown in Figure 33. DIO5 connects to both the DI and DO pins of the three-wire device. The CS pin
must be connected to a vacant DIO pin of the 78M6612. A pull-up resistor of roughly 10 kΩ to V3P3D
(to ensure operation in BROWNOUT mode) should be used for the DI/DO signals, and the CS pin should
be pulled down with a resistor to prevent that the 3-wire device is selected on power-up, before the
78M6612 can establish a stable signal for CS. The DIO_EEX register in I/O RAM must be set to 10 in
order to convert the DIO pins DIO4 and DIO5 to µWire pins. The pull-up resistor for DIO5 may not be
necessary.
V3P3D
78M6612
10kΩ
10kΩ
EEPROM
SCLK
DI
DIO4
DIO5
DIOn
DO
CS
Figure 33: 3-Wire EEPROM Connection
3.9 UART0 (TX/RX)
The RX pin should be pulled down by a 10 kΩ resistor and additionally protected by a 100 pF ceramic
capacitor, as shown in Figure 34.
78M6612
10kΩ
100pF
RX
RX
TX
Figure 34: Connections for the RX Pin
TX
70
Rev. 1.2