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National Instruments Corporation
25
NI Digital Waveform Generator/Analyzer Guide
Tables 8 and 9 describe the different conditions indicated by the two
NI PXI LEDs.
1, 4, 7, 10, 13,
16, 19, 22, 25,
28, 31, 34, 37,
40, 43, 46, 49,
52, 55, 58
GND
Ground
Ground reference for signals.
11, 12, 68, 69
RESERVED
N/A
These terminals are reserved for
future use. Do not connect to
these pins.
Table 7.
NI 654
X
/655
X
/656
X
SMB Connectors
Connector
Signal
Name
Signal
Type
Description
CLK IN
Reference/
Clock Input
Control
Terminal for the external Reference
clock used for the PLL or for the
external Sample clock used for
pattern generation and/or
acquisition.
PFI 0
Programmable
Function
Interface
(PFI) 0
Control
Input terminal to the device for
external triggers, or output terminal
from the device for events.
CLK OUT
Reference/
Clock Output
Control
Terminal for the exported PLL
Reference clock or the exported
Sample clock.
Table 8.
ACTIVE LED Indicators
Color
Indications
Off
Device not armed, not triggered, or experiencing an error.
Amber
Device armed and awaiting Start trigger. If performing a
dynamic acquisition operation, the device may be acquiring
pretrigger samples.
Green
Device received Start trigger.
Red
Error condition.
Table 6.
NI 656
X
DDC Connector Pins (Continued)
Pins
Signal Name
Signal
Type
Signal Description
