Chapter 3
Signal Connections
PCI-DIO-96/PXI-6508/PCI-6503 User Manual
3-8
ni.com
Note
Table 3-3 shows both the port C signal assignments and the terminology correlation
between different documentation sources. The 82C55A terminology refers to the different
82C55A configurations as modes whereas NI-DAQmx, Traditional NI-DAQ (Legacy),
LabWindows/CVI, and LabVIEW documentation refers to them as handshaking and no
handshaking. On the PCI-DIO-96 and PXI-6508, these signal assignments are the same for
all four 82C55A PPIs. Refer to Table 3-1 for more information.
Digital I/O Signal Connections
Pins 1 through 48 and, on the PCI-DIO-96 and PXI-6508, pins 51 through
98 of the I/O connector are digital I/O signal pins. The following
specifications and ratings apply to the digital I/O lines. The maximum input
logic high and output logic high voltages assume a V
cc
supply voltage of
5.0 V.
The absolute maximum voltage rating is
−
0.5 to +5.5 V with respect to
GND. For more information on the digital I/O signal specifications, refer to
Appendix A,
Table 3-3.
Port C Signal Assignments
Configuration Terminology
Signal Assignments
82C55A/
PCI-DIO-96/
PXI-6508/
PCI-6503
User Manual
National
Instruments
Software
APC7,
BPC7,
CPC7,
or
DPC7
APC6,
BPC6,
CPC6,
or
DPC6
APC5,
BPC5,
CPC5,
or
DPC5
APC4,
BPC4,
CPC4,
or
DPC4
APC3,
BPC3,
CPC3,
or
DPC3
APC2,
BPC2,
CPC2,
or
DPC2
APC1,
BPC1,
CPC1,
or
DPC1
APC0,
BPC0,
CPC0,
or
DPC0
Mode 0
(Basic I/O)
No
Handshaking
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
Mode 1
(Strobed Input)
Handshaking
I/O
I/O
IBF
A
STB
A
*
INTR
A
STB
B
*
IBFB
B
INTR
B
Mode 1
(Strobed
Output)
Handshaking
OBF
A
*
ACK
A
*
I/O
I/O
INTR
A
ACK
B
*
OBF
B
*
INTR
B
Mode 2
(Bidirectional
Bus)
Handshaking
OBF
A
*
ACK
A
*
IBF
A
STB
A
*
INTR
A
I/O
I/O
I/O
Notes
: Indicates that the signal is active low.
Subscripts A and B denote port A or port B handshaking signals.