Panasonic F77G User Manual page 438

Chapter 13 Serial Interface 4
Setup Procedure
(5) Set the slave address.
SC4AD0 (x'3FA3')
bp7-1 : I2CAD7-1 = 0110011
(6) IIC communication start
(7) Data transmission/reception
confirmation
SC4STR (x'3FAC')
bp7
(8) Transmission data setup
SC4TXB (x'3FA5')
bp7-0 : I2CTXB7-0 = x'55'
The transfer rate at IIC communication should be set to under 10 dividing of the system clock.
When master node on the IIC bus issues restart condition at slave transmission, as dummy
data, the upper bit should be "1" for transmission data buffer.
XIII - 12
Operation
: WRS = 0
Description
(5) Set the slave address to the upper 7 bits of the
SC4AD0 register (I2CAD7-1).
(6) Master on the IIC bus starts communication.
(7) When the address transmitted from the master
and the slave address set in the SC4AD1
register match, serial interface 4 interrupt
(SC4IRQ) is generated.
In the interrupt routine, make sure the
communication is the slave transfer by
verifying that the WRS flag of SC4STR
register is "0".
(8) Set the transmission data to the SC4TXB
register.