From: CTRInsurgent on
This page describes the HID.DLL API. I'm having a similar problem - I'm
guessing you also bought a cheapo USB-GPIB adapter from Australia? ;)
If I figure out the protocol, maybe I'll write a VI for it and post it on the
web. <a href="http://www2.hawaii.edu/%7Ehermany/api.htm" target="_blank">http://www2.hawaii.edu/~hermany/api.htm</a>
From: rolfk on
CTRInsurgent wrote:
This page describes the HID.DLL API. I'm having a similar problem - I'm guessing you also bought a cheapo USB-GPIB adapter from Australia? ;) If I figure out the protocol, maybe I'll write a VI for it and post it on the web. <a href="http://www2.hawaii.edu/~hermany/api.htm" target="_blank">http://www2.hawaii.edu/~hermany/api.htm</a>


HID is just the generic protocol for slow Human Device Interfaces. As such you can look at it in a similar way to TCP/IP. It defines how messages are transported over the network, but not what messages. The "what messages" is the device specific protocol, and here every manufacturer is quite free to define it's own protocol. There are a few standardized ones such as for a pointing device (mouse) or a keyboard, but one can define it's own too.
HID is slow so your cheapo GPIB interfaces will be slow too and I mean really slow in comparison to a NI GPIB interface. The reason manufacturers sometimes use a HID&nbsp;based protocol is because there is already a HID device kernel driver, so that one does not need to develop its own kernel device driver, which is a somewhat intimidating experience. But I'm not sure I would like a hardware from someone who isn't able to develop a real kernel device driver for his industrial product.
Rolf Kalbermatter