National Instruments 6508 PCI-DIO-96 - Manual (Page 67)

Chapter 6 Programming
© National Instruments Corporation 6-21 PCI-DIO-96 User Manual
Mode 1 Strobed Input Programming Example
The following example shows how to set up interrupts for mode 1 input
for port A.
Write (8255Cnfg, 0xB0) Set mode 1-port A is an input
Write (8255Cnfg, 0x09) Set PC4 to enable interrupts
from the 82C55A
Write (IREG2, 0x04) Set INTEN bit
Write (IREG1, 0x01) Set AIRQ0 to enable PPI A,
port A interrupts
Mode 1 Strobed Output Programming Example
The following example shows how to set up interrupts for mode 1
output for port A.
Write(8255Cnfg, 0xA0) Set mode 1-port A is an output
Write(8255Cnfg, 0x0D) Set PC6 to enable interrupts
from 82C55A
Write(IREG2, 0x04) Set INTEN bit
Write(IREG1, 0x01) Set AIRQ0 to enable PPI A,
port A interrupts
Mode 2 Bidirectional Bus Programming Example
The following example shows how to set up interrupts for mode 2
output transfers.
Write (8255Cnfg, 0xC0) Set mode 2 — port A is
bidirectional
Write (8255Cnfg, 0x0D) Set PC6 to enable interrupt
from 82C55A
Write (IREG2, 0x04) Set INTEN bit
Write (IREG1, 0x01) Set AIRQ0 to enable PPI A,
port A interrupts
The following example shows how to set up interrupts for mode 2 input
transfers.
Write (8255Cnfg, 0xC0) Set mode 2 - port A is
bidirectional
Write (8255Cnfg, 0x09) Set PC4 to enable interrupt
from 82C55A
Write (IREG2, 0x04) Set INTEN bit
Write (IREG1, 0x01) Set AIRQ0 to enable PPI A,
port A interrupts