Datasheet

Software-Controlled Switches (SoftConfig)
2-8 WVGA/LCD EI3 Extender Board Manual
electronic bus switches via TWI. The device has the following program-
ming characteristics:
• There are seven programmable GPIO registers.
• Each GPIO register controls eight signals (software switches).
• By default, the GPIO signals function as input signals; therefore,
all electronic switches are in the OFF state.
The signals must be programmed as output signals to override their
default values. The following table shows the register addresses and
values that must be written to them to program the signals as out-
put signals.
GPIO Register Register Address
GPIOA 0x03
GPIOB 0x05
GPIOC 0x07
GPIOD 0x09
GPIOE 0x0b
GPIOF 0x0d
GPIOG 0x0f
IODIR Register IODIR Register Address Value to be Written to Program Signals
as Outputs
IODIRA 0x02 0
IODIRB 0x04 0
IODIRC 0x06 0
IODIRD 0x08 0
IODIRE 0x0a 0