Oki MSM66591, User Manual

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MSM66591/ML66592 User's Manual
Chapter 6 Port Functions
6
6.12 Port 9 (P9)
Port 9 (P9_0 – P9_7) is an 8-bit I/O port. Input or output can be specified for each bit by
the Port 9 mode register (P9IO).
In addition to the port function, a secondary function (serial port I/O, etc) is assigned to
Port 9. Port function/secondary function is selected by the Port 9 secondary function
control register (P9SF).
Figure 6-15 shows the configuration of the Port 9 data register (P9), the Port 9 mode
register (P9IO), and the Port 9 secondary function control register (P9SF).
Figure 6-15 Configuration of P9, P9IO, and P9SF
P9_7 P9_6 P9_5 P9_4 P9_3 P9_2 P9_1 P9_0
7 6 5 4 3 2 1 0
P9
P9IO7 P9IO6 P9IO5 P9IO4 P9IO3 P9IO2 P9IO1 P9IO0
7 6 5 4 3 2 1 0
P9IO
P9_n = input 0
P9_n = output 1
n = 0–7
P9SF
7 6 5 4 3 2 1 0
ECTCK ETMCK TXD4 RXD4 TXD3 RXD3 TXD2 RXD2
0 P9_0
1 Serial port 2 receive data input
0 P9_1
1 Serial port 2 transmit data output
0 P9_2
1 Serial port 3 receive data input
0 P9_3
1 Serial port 3 transmit data output
0 P9_4
1 Serial port 4 receive data input
0 P9_5
1 Serial port 4 transmit data output
0 P9_6
1 External clock input for general
-purpose 8-bit timer
0 P9_7
1 External clock input for general
-purpose 8-bit event counter