National Instruments PC-DIO-96 Manual Do Utilizador
Chapter 4
Register-Level Programming
© National Instruments Corporation
4-11
PC-DIO-96 User Manual
Table 4-3. Mode 0 I/O Configurations
Control Word
Group A
Group B
Number
Bit
Port A
Port C
1
Port B
Port C
2
76543210
0
10000000
Output
Output
Output
Output
1
10000001
Output
Output
Output
Input
2
10000010
Output
Output
Input
Output
3
10000011
Output
Output
Input
Input
4
10001000
Output
Input
Output
Output
5
10001001
Output
Input
Output
Input
6
10001010
Output
Input
Input
Output
7
10001011
Output
Input
Input
Input
8
10010000
Input
Output
Output
Output
9
10010001
Input
Output
Output
Input
10
10010010
Input
Output
Input
Output
11
10010011
Input
Output
Input
Input
12
10011000
Input
Input
Output
Output
13
10011001
Input
Input
Output
Input
14
10011010
Input
Input
Input
Output
15
10011011
Input
Input
Input
Input
1
Upper nibble of port C
2
Lower nibble of port C
Mode 0 Programming Example
The following example shows how to configure PPI A for various combinations of mode 0 input
and output. This code is strictly an example and is not intended to be used without modification
in a practical situation.
and output. This code is strictly an example and is not intended to be used without modification
in a practical situation.
Main() {
#define BASE_ADDRESS
0x180
/* Board located at address 180 */
#define APORTAoffset
0x00
/* Offset for PPI A, port A */
#define APORTBoffset
0x01
/* Offset for PPI A, port B */
#define APORTCoffset
0x02
/* Offset for PPI A, port C */
#define ACNFGoffset
0x03
/* Offset for PPI A, CNFG */
unsigned int porta, portb, portc, cnfg;
char valread;
char valread;
/* Variable to store data read from a
port */
/* Calculate register addresses */