ACCES I/O Products, Inc.
MADE IN THE USA
USB-AI16-2A
4
manual revision A1d
C
HAPTER
5:
PC
I
NTERFACE
The USB-AI16-2A is a USB 2.0 High-Speed device compatible with
2.0 and 3.0 USB ports.
The ubiquitous USB port provides a convenient and hot-pluggable
interface for adding this high-speed analog input board to almost
any system.
In addition to the industry standard type-B USB connector an
alternate micro-fit embedded USB header connector is
provided. This connector provides a very small footprint,
latching signal interface that avoids the stiff and bulky USB
cable.
The USB-AI16-2A can be powered via the USB cable (a powered
USB port is required), or from ex5VDC power supplied
via either a DC-jack (option -PR) or screw terminals (option -ST).
C
HAPTER
6:
I/O
I
NTERFACE
A total of three I/O connectors are provided on this device. A 16-
pin right-angle shrouded and keyed male 0.1” spacing IDC header
contains the digital I/O bits. A pair of BNC connectors are used to
connect analog inputs.
The pair of BNC connectors are industry standard “female”
identical to those you would find on test equipment anywhere.
All DIO bits can be pulled up or down via jumper selection (in two
groups of four bits each). Pull-ups are generally used with input
mode (to make contact-closure monitoring easy), while outputs
are best configured for pull-downs (so external devices don’t
activate while the computer is booting).
All pull-up/pull-down resistors for the Digital Inputs and Outputs
are 10kΩ. The GATE signal input is pulled up, active high, and
allows conversions to occur following software command.
Grounding this input will disable A/D conversions. The /FIFO FULL
signal is active low indicating the data FIFO is almost full. The
/RUNNING signal is active low indicating conversions are software
enabled.
C
HAPTER
7:
S
OFTWARE
I
NTERFACE
The USB-AI16-2A utilizes a high-speed custom function driver
optimized for maximum continuous data throughput that is
hundreds to thousands of times faster than the USB human
interface device (HID) driver used by many competing products.
This approach maximizes the full functionality of the hardware
along with capitalizing on the advantage of high-speed USB 2.0.
The boards are supported for use in most USB supported operating
systems and includes a free Windows and Linux compatible
software package. This package contains sample programs and
source code in C# (.NET), Delphi, and Visual C++, for Windows.
Pin
Signal
Names
Description
Pin
Signal
Names
Description
1
DI 0
Digital Input0 2
DI 1
Digital Input1
3
DI 2
Digital Input2 4
DI 3
Digital Input3
5
GND
Ground
6
GND
Ground
7
DO 0 Digital Output0 8
DO 1
Digital Output1
9
DO 2 Digital Output2 10
DO 3
Digital Output3
11
GND
Ground
12
GND
Ground
13
GATE
ADC Gate
14 /RUNNING ADC Status
15
/FIFO
FULL
FIFO FULL
16
GND
Ground
Option Selection Map & Dimension Drawing
