Port - Toshiba TMP91C815F Data Book

3.5.1 Port 1 (P10 to P17)
Port 1 is an 8-bit general-purpose I/O port. Each bit can be set individually for input or output using the
control register P1CR. Resetting , the control register P1CR to "0" and sets Port 1 to input mode.
In addition to functioning as a general-purpose I/O port, Port 1 can also function as data bus (D8 to 15).
Reset
Direction
control
(on bit basis)
P1CR write
Output Latch
P1 write

Port 1

P10 to P17
Output buffer
(D8 to D15)
P1 Read
Figure 3.5.1 Port 1
91C815-55
TMP91C815