Intel 8XC196NT, User Manual

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C-37
REGISTERS
Px_DIR
P
x
_DIR
x = 1, 2, 5, 6
Address:
Reset State:
Table C-8
Each pin of port x can operate in any of the standard I/O modes of operation: complementary output,
open-drain output, or high-impedance input. The port x I/O direction (P x _DIR) register determines the
I/O mode for each port x pin. The register settings for an open-drain output or a high-impedance input
are identical. An open-drain output configuration requires an external pull-up. A high-impedance input
configuration requires that the corresponding bit in P
x _REG be set.
7 0
x
= 1, 2, 5, 6 PIN7 PIN6 PIN5 PIN4 PIN3 PIN2 PIN1 PIN0
Bit
Number
Bit
Mnemonic
Function
7:0 PIN7:0 Port x Pin y Direction
This bit selects the P x . y direction:
1 = input/open-drain output (input, output, or bidirectional)
0 = complementary output (output only)
Table C-8. P x_DIR Addresses and Reset Values
Register Address Reset Value
P1_DIR 1FD2H FFH
P2_DIR 1FCBH 7FH
P5_DIR 1FF3H FFH
P6_DIR 1FD3H FFH