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Analog output, External clock i/o, Digital i/o – Measurement Computing E-1608 User Manual

Page 15: Pull-up/down configuration

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E-1608 User's Guide

Functional Details

15

Analog output

Two 16-bit analog outputs are available at AOUT0 and AOUT1.

Each analog output channel has an output range of ±10 V. Throughput is system-dependent.

The D/A is software-paced. Each 16-bit analog output (

AOUT0

and

AOUT1

) can be updated simultaneously at

rates from 1000 S/s to 5000 S/s. This is the typical throughput when the device and host are both hard-wired to
the same local network. Typical throughput is not guaranteed if a wireless connection is involved or data is sent
over the Internet.

External clock I/O

The E-1608 provides one external clock input (

AICKI

) and one clock output (

AICKO

) for analog inputs.

 You can connect an external clock signal to

AICKI

.

 When using the internal clock,

AICKO

outputs the

ADC scan clock.

Digital I/O

You can connect up to eight digital I/O lines to

DIO0

through

DIO7

. Each digital channel is individually

configurable for input or output. The digital I/O terminals can detect the state of any TTL-level input and offer .
advanced BiCMOS output.

Refer to the schematic shown in Figure 5.

Figure 5. Schematic showing switch detection by digital channel DIO0

If you set the switch to the +5 V input, DIO0 reads TRUE (1). If you move the switch to GND, DIO0 reads
FALSE (0).

Pull-up/down configuration

Unconnected inputs are pulled high by default to 5 V through 47 kΩ resistors via jumper

W3

on the circuit

board (see Figure 6).

1

W3 pull-up/pull-down jumper

Figure 6. W3 jumper location

The pull-up/pull-down voltage is common to all 47 kΩ resistors. Jumper W3 is configured by default for pull-
up.