RB-730 button release with Presentation

I have a RB-730 response pad that is used with Presentation. The Presentation Extension allows me very easily to use the response pad with Presentation. However this only works for button presses. Button releases are not detected at all. Indeed the list of available buttons shown in Presentation’s response window only shows a single entry for each key. Is there a fix for this so that I can use button releases as well as presses?

As a Plan B, if I delete the Presentation Extension and set up a serial port “longhand”, button presses and button releases are both recognised. However, the codes generated are inconsistent and rather meaningless. I have tried every combination of parameters (baud rate etc) and configurations but have been unable to to find a configuration that generates usable codes in Presentation.

Running under an old Windows XP system I had no problems in the past. The response device itself is rather old (~2007 I think), so I have had to update it to run on Windows 7. The upgrade (using the instructions and software provided by Cedrus) was successful, but could this update be somehow incompatible with Presentation?

Alas, you are correct that the button press feature is not implemented in the Presentation plug-in.

Your serial port “longhand” Plan B should work. The reason the codes generated seem inconsistent is because they are time-stamped, so a different six-byte code is generated every time you press a key. See this page about the XID Supported Protocols for a description of the six-byte format.

You might also find the open source code helpful.

As for updating the response pad for Windows 7 compatibility and the instructions published on our website, all the update does is change the USB manufacturer ID; this tells Windows which USB driver it should look for. There is no change at all to the firmware itself.

Thanks for the info. One final question - in the past when the device was connected via a serial port Presentation used to automatically recognise 14 possible inputs, i.e. a press and release code for each of the 7 buttons. This was without any recourse to Presentation Extensions. Now Presentation merely offers the values from 0 to 255. What has changed? Is it the Presentation version, or the Windows version? Or is there a way to revert to the original bevaviour, perhaps by setting appropriate DIP switches?

Ah, you make a good point, and I should have mentioned this before. If you are going to communicate with the response pad directly, it is probably a good idea to use a mode other than XID mode. The other modes do not have time stamping.

If you want to detect button presses, I suggest you use the RB-x20 mode. See the Response Pad DIP Switches page. In this mode, you receive one byte each time a key is pressed or released. Each bit within that byte indicates the status of the corresponding key, i.e. whether it is up or down.

Ah, yes. The RB x20 mode works. Thanks!