National Instruments Low-Cost Multifunction I/O Board for ISA Lab-PC+ - Manual (Page 44)

Chapter 3 Signal Connections
© National Instruments Corporation 3-13 Lab-PC+ User Manual
Pin 11, AGND, is the ground reference point for both analog output channels as well as analog
input.
The following output ranges are available:
Output signal range Bipolar input:
±
5 V *
Unipolar input: 0 to 10 V *
* Maximum load current =
±
2 mA for 12-bit linearity
Figure 3-7 shows how to make analog output signal connections.
10 DAC0 OUT
Channel 0
Channel 1
Analog Output Channels
Lab PC+ Board
DAC1 OUT
AGND
11
12 +
+
-
-
VOUT 1
VOUT 0 Load
Load
Figure 3-7. Analog Output Signal Connections
Digital I/O Signal Connections
Pins 13 through 37 of the I/O connector are digital I/O signal pins. Digital I/O on the Lab-PC+ is
designed around the 8255A integrated circuit. The 8255A is a general-purpose peripheral
interface containing 24 programmable I/O pins. These pins represent the three 8-bit ports (PA,
PB, and PC) of the 8255A.
Pins 14 through 21 are connected to the digital lines PA<0..7> for digital I/O Port A. Pins 22
through 29 are connected to the digital lines PB<0..7> for digital I/O Port B. Pins 30 through 37