bmcm USB-PIO User manual

USB-PIO
Digital I/O Interface (USB)
24 Channels. Digital.
Signal Output & Monitoring.
Record and output digital TTL signals. The
USB-PIO features three 8-bit bidirectional
ports. The port lines are led out to a 25-pin D-
Sub female connector.
Extra Small. Extra Red.
Extra Low-Priced.
The unique idea of the USB-PIO: the device is
accommodated in the D-Sub connector
housing. Not only the size is extra small but
also the price.
Plug & Play.
The connection to the PC is realized via USB.
The USB-PIO provides all typical USB features
(e.g. Plug&Play, Hot-Plug). Up to 127 devices
can be connected and installed during
operation.
Powered by USB.
The device is supplied with power via the USB
interface. This reduces cabling efforts to a
minimum and makes mobile measurements a
lot easier.
Open for Everyone.
Widely supported: The USB-PIO can be used
under Windows®XP/7/8/10 as well as under
Mac OS X, Free BSD, and Linux. The
complete software for installation and
programming of the device is included for free.
NextView®. Try for Free.
The DAQ system is supported by NextView®,
the software for data acquisition and analysis.
A fully functional 14-day trial is included with
delivery to directly test the functionality of the
USB-PIO.
Get Connected.
Various optocoupler and relay cards are
available at bmcm to electrically isolate the
digital lines. For the USB-PIO it is particularly
easy as only a 25-pin D-Sub extension cable
is needed for connecting.
Functional diagram and pin assignment

USB-PIO
Page 2
1 Start-up procedure
All available software and documentation for the USB-PIO are located on www.bmcm.de/usb-pio-en
in the tab
Downloads.
1. Step: Installation device driver
Install the latest driver package in order to use the USB measurement device. You
will find the package on www.bmcm.de/usb-pio-en in the tab
Downloads
in the
category
BMCM – Drivers
. Open the manual device drivers on www.bmcm.de/man-
driver for more information.
2. Step: Connect up
Connect the provided USB cable to the device and to a free USB port of the PC.
Then start the plug and play installation. The device gets its power supply through
the USB connection.
3a. Step: Measuring with NextView
To be able to use your measurement system with NextView, you just need to
download and install the latest version of NextView on www.nextview.de/download-
en.html. In case you did not buy NextView, request a free of charge trial version
when first starting NextView. Find more information about NextView and its
installation on www.nextview.de or in the manual on www.bmcm.de/man-nextview.
3b. Step: Measuring with API
In case you want to use the measurement device without NextView, you need to download
and install the free of charge programming interface LIBAD4. You can find this on
www.bmcm.de/usb-pio-en in the tab
Downloads
in the category
LIBAD – Programming
Interface (API)
, too. Find more information on www.bmcm.de/libad-en or directly in the
manual www.bmcm.de/man-libad.

USB-PIO
Page 3
2 Digital Inputs and Outputs
The USB-PIO features a µ-controller providing three 8-bit digital ports A, B, C. The lines are
bidirectional. The direction is set to input or output in groups of 8 (port C: 4) via software.
The following table and figure shows the pin assignment of the 25-pin D-Sub female connector of the
USB-PIO, at which the digital lines are accessible.
Pin (D-Sub 25)
Port / Bit
Pin (D-Sub 25)
Belegung
1
A/0
9
C/0
14
A/1
22
C/1
2
A/2
10
C/2
15
A/3
23
C/3
3
A/4
11
C/4
16
A/5
24
C/5
4
A/6
12
C/6
17
A/7
25
C/7
5
B/0
13
digital ground
(DGND)
18
B/1
6
B/2
19
B/3
7
B/4
20
B/5
8
B/6
21
B/7
• Always turn on the PC first before applying voltage to the digital lines.
• Do not apply voltage to the ports without the relevant protective circuit. Two outputs connected with each other may
get damaged by the high flow of current.
• The digital inputs are equipped with an internal 100k
W
pull-down resistor for open inputs to be constantly low.
• After power-on, the direction of the digital channels is always set to input.

USB-PIO
Page 4
3 Interfacing Examples
3.1 Interfacing Examples for Digital Inputs
The 3.9kWpull-down resistor sets the input to low if no voltage is applied there.
3.1.1 Connecting an Optocoupler
Optocouplers provide optimum protection at
each input line. With them, it is possible to
connect higher voltages and to protect the
hardware from being destroyed.
In this regard, please also see application
examples of the optocoupler you use.
Optocoupler cards featuring 8 inputs are available
at bmcm (see chapter 6).
3.1.2 Connecting a Push-Button / Switch
Please make sure to use a push-button with
debounce protection, because otherwise
several pulses might be recorded.
Although a 100kWpull-down resistor is
integrated, an external 3.9kWpull-down can
increase the safety of the circuit.
3.1.3 Connecting a Voltage Divider
If connecting a DC voltage higher than 5V, a
voltage divider must be used so that 5V at
the maximum are applied at the device
input. Exceeding the 5V input voltage might
cause damages to the device.
The relation between the two resistors to be
used is calculated with the following formula:
U/U1= (R1+R2)/R1
Input voltages less than 5V are also
sufficient (high ³3V).

USB-PIO
Page 5
3.2 Interfacing Examples for Digital Outputs
Serial resistors in the output lines limit the current and protect the hardware from being destroyed.
3.2.1 Connecting an LED
Only so-called low-current LEDs can be used,
because they already work with 1mA current.
Please also observe the total current listed in
the technical data (see chapter 0).
3.2.2 Connecting a Relay
A connected relay is ideal to switch higher
currents. Since the field coil of the relay
requires a higher current than provided by the
measurement system at one line, a transistor
is connected ahead.
Relay cards featuring 8 outputs are available at bmcm
(see chapter 6).
3.2.3 Connecting a Lamp
A transistor can be used to switch higher
loads. The selected transistor must comply
with the maximum switchable current.
The figure on the right shows an application
with a maximum current of 100mA.

USB-PIO
Page 6
4 Connection Technology for USB-PIO
bmcm provides optocoupler and relay
cards to electrically isolate the digital
inputs and outputs of the USB-PIO.
The connectors are directly
compatible for a 25-pin D-Sub-
standard cable to be used. If
connecting several OR8, R8 to the
USB-PIO, a special cable has to be
made (see figure below).
Channel
OR8
R8
IN (optocoupler input)
8
-
OUT (relay output)
8
8
I/O (bidirectional)
-
-
• The port direction of the USB-PIO must comply with the settings of the optocoupler/relay card to avoid damages
(optocoupler channels to input, relay channels to output).
• For further information, please see the relevant data sheets.
Interfacing example

USB-PIO
Page 7
5 Important Notes for Using the USB-PIO
• The device is only suitable for extra-low voltages - please observe the relevant regulations! Only use the
device with housing closed. ESD voltages at open lines may cause malfunction.
• Only use non-solvent detergents for cleaning. The product is designed to be maintenance-free.
• Signal cables are connected at the 25-pin D-Sub female connector – preferably use shielded cables. For
best possible interference suppression, connect shield at one end only. Close open inputs if necessary.
• The device ground and the chassis are electrically connected to the chassis of the PC, which is usually also
connected to ground. Be sure to avoid ground loops since they will cause measuring errors!
• PCs (notebooks) which are not grounded often produce high potentials to earth at the USB socket so that
safe operation cannot be guaranteed. In this case, connect the measuring system to earth.
• The device must not be used for safety-relevant tasks. With the use of the product, the customer becomes
manufacturer by law and is therefore fully responsible for the proper installation and use of the product. In
the case of improper use and/or unauthorized interference, our warranty ceases and any warranty claim is
excluded.
Do not dispose of the product in the domestic waste or at any waste collection places. It has to be either
duly disposed according to the WEEE directive or can be returned to bmcm at your own expense.

USB-PIO
Page 8
6 Technical Data
(typical at 20°C, after 5min., +5V supply)
• Digital Inputs/Outputs
Lines:
3x 8 lines (bidirectional, set in groups of 8, port C in groups of 4)
Level:
CMOS/TTL compatible (low: 0V..0.7V; high: 3V..5V)
Current pick-up per output pin:
max. 5mA (with app. 4V-level), max. 20mA in total of all output channels!
Sampling rate:
up to 500 values/second can be sampled (depending on software and PC)
Input resistance:
100kWpull-down resistor (PC off: 1kW)
Surge protection:
max. ±5.5V, max. max. ±20mA in total of all channels!
USB interface:
USB 2.0 compatible (full-speed)
• General Data
Power supply:
+4.5V..+5.5V from USB connection to the PC, max. 100mA
Digital connections:
all 24 lines at 25-pin D-Sub female
CE standards:
EN61000-6-1, EN61000-6-3, EN61010-1; for decl. of conformity (PDF) visit www.bmcm.de
ElektroG // ear registration:
RoHS and WEEE compliant // WEEE Reg.-No. DE75472248
Max. permissible potentials:
60V DC acc. to VDE
, max. 1kV ESD on open lines
Temperature ranges:
operating temp. 0..70C, storage temp. –25..+70C
Relative humidity:
0-90% (not condensing)
Dimensions:
53 x 44 x 16 mm3, USB cable app. 1.1m
Protection type:
IP30
Delivery:
device in plastic housing with USB cable
Available accessories (optional):
connecting cable ZUKA25, 25-pin D-Sub plug ZU25ST, optocoupler/relay cards OR8, R8
Warranty:
2 years from date of purchase at bmcm, claims for damages resulting from improper use excluded
• Software
Software free of charge download:
LIBAD4 SDK for C/C++ programming on Windows® XP/7/8/10, Mac OS X, Unix (FreeBSD, Linux);
trial version of the measuring software NextView®to test and operate the hardware
NextView®(optional):
professional software (versions: Professional, Lite) for the acquisition and analysis of measurement data on
Windows®8/10
Manufacturer: BMC Messsysteme GmbH. Subject to change due to technical improvements. Errors and printing errors excepted. Rev. 6.2
02/11/2020