National Instruments 653 Series User Manual page 102

Pins Signal Name
23, 57–58, DIOC<0..7>
25–26,
60–61, 28
29, 63–64, DIOD<0..7>
31–32,
66–67, 34
40 CPULL
38 DPULL
1 +5 V
11, 14, 18, GND
20, 24, 27,
30, 36–37,
39, 41–42,
46, 49–50,
55, 59, 62,
65, 68
19, 35, 43, RGND
56
© National Instruments Corporation
Table C-3. Signal Descriptions (Continued)
Signal
Type
Data Port C bidirectional data lines
Port C is referred to as port number 2 in software. DIOC7 is the MSB;
DIOC0 is the LSB.
Data Port D bidirectional data lines
Port D is referred to as port number 3 in software. DIOD7 is the MSB;
DIOD0 is the LSB.
Bias Control pull-up/pull-down selection
Selection
Input signal that selects whether the NI 653X pulls the timing and handshaking
control lines (REQ, ACK, PCLK, and STOPTRIG) up or down when the lines
are not driven. If you connect CPULL to +5 V on the external terminal
connector, the NI 653X pulls the control lines up. If you connect CPULL to
GND or leave CPULL unconnected, the NI 653X pulls the control lines down.
Refer to power on state the
Considerations, for more information.
Bias Data pull-up/pull-down selection
Selection
Input signal that selects whether the NI 653X pulls the data lines (DIOA,
DIOB, DIOC, and DIOD) up or down when the lines are not driven. If you
connect DPULL to +5 V on the external terminal connector, the NI 653X pulls
the data lines up. If you connect DPULL to GND or leave DPULL
unconnected, the NI 653X pulls the data lines down.
Refer to power on state the
Considerations, for more information.
Power 5 V output
Line that provides a maximum of 1 A of power. This line is protected by an
onboard fuse that shuts off power when there is too much current and
automatically resets itself after current returns to normal.
Power Ground
These lines are the ground reference for all other signals.
Power Reserved ground
These lines offer additional ground pins. If you are using an R6868 ribbon
cable for example, these lines can be used as additional ground references.
If you are using an SH68-68-D1, however, these signals are not connected.
Appendix C
Signal Description Based on Mode Used
Power-On State
Power-On State
C-5
Connecting Signals with Accessories
section of Appendix D, Hardware
section of Appendix D, Hardware
NI 653X User Manual