Product model: Velleman K8055
Product type: I/O card kit that plugs to PC USB port
Manufacturer: Velleman
http://www.velleman.be/
Price: around 40 Euros
Product home page:
http://www.velleman.be/common/product.a ... &id=351346
Supported operating systems: Windows 98SE or higher
Short description:
The K8055 interface board has 5 digital input channels and 8 digital output channels. In addition, there are two analogue inputs and two analogue outputs with 8 bit resolution. The number of inputs/outputs can be further expanded by connecting more (up to a maximum of four) cards to the PC's USB connectors. All communication routines are contained in a Dynamic Link Library (DLL). You may write custom Windows (98SE, 2000, Me, XP) applications in Delphi, Visual Basic, C++ Builder or any other 32-bit Windows application development tool that supports calls to a DLL.
The price of the kit is around 40 Euros / Dollars.
Comments:
Kit works as promised. It was easy to build and take into use. The drivers and software worked pretty well with Windows 2000 operating system.
Control program allows you to easily control the card and see the state of the inputs/outputs. It was easy to use.
The card also comes with Dynamic Link Library (DLL) that is promised to allow you to write custom Windows (98SE, 2000, Me, XP) applications in Delphi, Visual Basic, C++ Builder or any other 32-bit Windows application development tool that supports calls to a DLL. I have not tested those programming tools yet.
The inputas are easy to test without any extra hardware. There are test buttons for activating the different inputs. There are also trimmers that you can use use to send different voltages to card A/D inputs. The card outputs have also indicator LEDs in the.
The digital input and outputs are implemented with ULN2803 IC. For output this gives out enough drive capacity to drive many kinds of small loads and/or relays. The IC has built-in protection against relay inductive spikes (if you wire it correctly). The control outputs are open collector type, which means that the relays can operate at different voltage than rest of circuitry (for example 12V or 24V relays can be controlled when you have a suitable external power supply for them). The IC is installed on the socket, so it is easy to change if it gets damaged for some reason.
The inputs are also based on ULN2803 IC, which it should be pretty well protected as well (should not be damaged if accindetally voltages to it ger slightly past +5V I quess..).
Other comments:
Velleman seems to sell this same product also as ready made module with product code VM110
http://www.velleman.be/common/product.A ... &id=351980
And they also sell quite nice looking 8 relay module MV129 that can be conencted to VM110 (DIN rail mountable with sutiable Velleman case)
http://www.velleman.be/common/product.A ... &id=361120
I have not tested those ready made modules myself.
For Linux users there seems to be an open source project to make Linux drivers for this kit at
http://linuxk8055.free.fr/
I tried quicly to use those, but I did not get them working (did not compile properly on my Fedora Core 4 system).