Timing Specifications For Digital I/O Ports A, B, And C; Table 4-5. Port C Signal Assignments - National Instruments AT-MIO/AI E Series User Manual

Timing Specifications for Digital I/O Ports A, B, and C

Programming
Mode
Mode 0
Mode 1 Input
Mode 1 Output
Mode 2
* Indicates that the signal is active low.
National Instruments Corporation
AT-MIO-16DE-10 only
In addition to its function as a digital I/O port, digital port C,
PC<0..7>, can also be used for handshaking when performing data
transfers with ports A and B. The signals assigned to port C depend
on the mode in which it is programmed. In mode 0, port C is
considered two 4-bit I/O ports. In modes 1 and 2, port C is used for
status and handshaking signals with two or three additional I/O
bits. Table 4-5 summarizes the signal assignments of port C for
each programmable mode.
Table 4-5. Port C Signal Assignments
Group A
PC7 PC6 PC5
I/O I/O I/O
I/O I/O IBF A
OBF A * ACK A * I/O
OBF A * ACK A * IBF A
PC4 PC3
I/O I/O
STB A * INTR A
I/O INTR A
STB A * INTR A
4-53
Chapter 4 Signal Connections
Group B
PC2 PC1 PC0
I/O I/O I/O
STB B * IBFB B INTR B
ACK B * OBF B * INTR B
I/O I/O I/O
AT-MIO/AI E Series User Manual