NEWS

5/3/07 New Chassis for Serial Button Box! See below...

K4308-1 (a super-speedy serial button box)

 

 

 

It turns out that our USB response boxes have been immensely popular. The USB standard allows for easy plug and play operation and you don't need to worry about installing complicated drivers or other software. These boxes just work.

Unfortunately, there are some drawbacks to using a USB interface. Most importantly, USB is a polling system. This means that the host computer is responsible for initiating all communication between peripheral devices. With only one or two exceptions, all standard keyboards and mice operate as 'low speed' devices. This means that the host computer will only poll the keyboard or mouse once every ten milliseconds.

Which leads to latency in timing measurements.

Because it's unclear where the host computer is in the polling loop, these measurements have an uncertainty of +/- 10 mS. For some research projects, this isn't a problem. However, other situations demand greater precision. For this reason, we designed a button box which interfaces with the computer's serial port.

It requires a few quick changes to the computer's COM port settings when first installed, but otherwise operates very cleanly. It plays very well with Empirisoft's DirectRT software.

And check out these timing specifications:

The work surface of this box measures 10" x 7", and slopes upward at a 15 degree angle.