Справочник Пользователя для National Instruments PC-DIO-24
Chapter 4
Register-Level Programming
© National Instruments Corporation
4-5
PC-DIO-24 User Manual
Table 4-2. Port C Set/Reset Control Words
Number
Bit Set
Bit Reset
Bit Set or
Control Word
Control Word
Reset in Port C
0
0xxx0001
0xxx0000
xxxxxxxn
1
0xxx0011
0xxx0010
xxxxxxnx
2
0xxx0101
0xxx0100
xxxxxnxx
3
0xxx0111
0xxx0110
xxxxnxxx
4
0xxx1001
0xxx1000
xxxnxxxx
5
0xxx1011
0xxx1010
xxnxxxxx
6
0xxx1101
0xxx1100
xnxxxxxx
7
0xxx1111
0xxx1110
nxxxxxxx
Programming Considerations
Mode 0–Basic I/O
Mode 0 can be used for simple I/O functions for each of the three ports with no handshaking.
Each port can be assigned as an input or an output port. The 16 possible I/O configurations are
shown in Table 4-3. Notice that bit 7 of the control word is set when programming the mode of
operation for each port.
Each port can be assigned as an input or an output port. The 16 possible I/O configurations are
shown in Table 4-3. Notice that bit 7 of the control word is set when programming the mode of
operation for each port.