© National Instruments Corporation 11 NI PCIe-8255R User Manual
references for the parameters you can set for the NI-IMAQ I/O device
in the Read/Write control. To locate the information, search for
"NI-IMAQ I/O" in LabVIEW Help.
Specifications
These specifications are typical at 25 °C, unless otherwise stated.

Power Requirements

IEEE 1394 bus power1...........................18 W, maximum
(sharedbybothports)
Isolated supply2......................................5 VDC to 30 VDC
Camera interface3...................................IEEE 1394b, compatible with
IEEE 1394a cameras

TTL Inputs and Outputs

Digital logic levels

TTL Inputs

Number of channels............................... 2
Maximum pulse rate...............................2 MHz
Minimum pulse detected........................500 ns
Power-on state........................................Input (high-impedance)
61.9 kΩpull-up to 5V
1 The bus power specification assumes that power is provided to the NI 8255R device from the host computer power supply via
the ATX power connector. If power is not supplied through the ATX power connector, camera power is supplied by the PCIe
bus and should be limited to 3 W, shared by both ports.
2 Do not draw more than 100mA from 30 V isolated outputs. Do not draw more than 50 mA from 5 V isolated outputs.
3 To connect an IEEE 1394a camera to the NI 8255R, you will need a 6-pin to 9-pin cable or a 6-pin to 9-pin adapter.
Level Minimum Maximum
Input low voltage (VIL)0 V 0.5 V
Input high voltage (VIH)2.2 V 5 V
Output low voltage (VOL), at 5 mA —0.4 V
Output high voltage (VOH), at 5 mA 2.4 V —