Figure B-6. Port C Pin Assignments On I/O Connector When Port C Configured For Mode 1 Input - National Instruments PCI-DIO-96 User Manual

Appendix B Register-Level Programming — Port C Status-Word Bit Definitions for Input (Ports A and B)
0
At the digital I/O connector, port C has the pin assignments shown in Figure B-6 when in
mode 1 input. Notice that the status of STBA* and the status of STBB* are not included in
the port C status word.

Figure B-6. Port C Pin Assignments on I/O Connector when Port C Configured for Mode 1 Input

Mode 1 Strobed Input Programming Example
The following example shows how to configure PPI A for mode 1 input.
Write (8255Cnfg, 0xB0) Set mode 1—port A is an input
Write (8255Cnfg, 0x09) Set PC4 to enable the INTRA status flag
Loop until the INTRA (PC3) and IBFA (PC5) status flags are set,
Read (PortA)
PCI-DIO-96/PXI-6508/PCI-6503 User Manual
INTRB Interrupt Request Status for Port B—Interrupt Request
Status for Port B. This status flag, which operates only
when INTEA is high, indicates that port B has acquired
data and is ready to be read. If you have enabled interrupts
(by setting INTEN and the appropriate bit in Interrupt
Control Register 2), this status flag also indicates that an
interrupt request is pending for port B.
Group A
Group B
indicating that the 82C55A is ready for a
transfer and that the input buffer is full
Read data from port A
PC7 I/O
PC6 I/O
PC5 IBFA
PC4 STBA*
PC3 INTRA
PC2 STBB*
PC1 IBFB
PC0 INTRB
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