Toshiba TMP91C815F Data Book page 66

(2) Port71 (SO/SDA/OPTTX0)
Port71 is a general-purpose I/O port. It is also used as SDA (data input for I
output for SIO mode) for serial bus interface and OPTTX0 (transmit output for IrDA mode of
SIO0).
Used as OPTTX0, it is possible to logical-invert by P7<P71>="0".
Reset
Function
control 2
(on bit basis)
P7FC2 write
Direction
control
(on bit basis)
P7CR write
Function
control
(on bit basis)
P7FC write
S
Output latch
P7 write
SO output
TXD0 output
logical invert
P7 read
SDA input
S
A
Selector
B
Open drain possible :
C
P7ODE<ODEP71>
S
B
Selector
A
Figure 3.5.13 Port 71
91C815-63
TMP91C815
2
C mode), SO (data
Programable
pull-up
P71
(SO/SDA,OPTTX0)