Hitachi H8S/2678 Series Reference Manual page 593

TDR0—Transmit Data Register 0
Bit
Initial value
Read/Write R/W
576
7 6
1 1
R/W R/W
Stores data for serial transmission
H'FF7B
5 4
1 1
R/W R/W
SCI0, Smart Card Interface 0
3 2
1 1
R/W R/W
1 0
1 1
R/W