
Appendix C Connecting Signals with Accessories
© National Instruments Corporation C-3 653X User Manual
Note In Figure C-1, the * indicates that you can reverse the pin assignments of the ACK1 
(STARTTIG1) and REQ1 pins, or the ACK2 (STARTTIG2) and REQ2 pins. To do this, set 
the ACK-REQ Exchange attribute to ON in the DIO Parameter VI in LabVIEW or in 
set_DAQ_Device_Info in NI-DAQ. This allows you to perform handshaking I/O 
between two 653X devices using an SH-68-68-D1 cable.
Use TableC-2 to find the accessories designed for connecting signals to 
your 653Xdevice.
Signal DescriptionsUse TableC-3 to find the function for each signal, which is based on the 
mode and protocol you are using. All the signals on the 653Xdevice are 
referenced to the GND lines.
Table C-2.  68-Pin Accessories
Device Shielded Cable Ribbon Cable Cable Adapter
PCI/PXI/AT/
Compact PCI
SHC68-68-D1—female 68-pin 
SCXI connectors on both ends 
of the cable
N/A N/A
DAQCard-6533 
for PCMCIA
PSHR68-68-D1 and
PSHR68-68M
PR68-68F N/A