Millisecond Forums

Hi Inquisit team,

We're using Inquisit (5) to control a device for electrical stimulation. For this, we built D/A-changers that transform the digital 8bit signal from Inquisit to an analogous +/-10V output. We had great success with a LPT changer and currently tried out an USB-based changer. The USB-changer has a built in FTDI232 chip and is recognized as COM4 on my PC (Windows 10). Other settings of the port are:
Baudrate: 57600
Bits: 8
Parity: none
Stoppbits: 1

While initially the D/A-changer was responding perfectly when using a terminal software to control it (e.g. HTerm [http://www.der-hammer.info/terminal/]), whenever we used Inquisit, the changer did receive the signals, but did not give any output, as the input was considered incorrect. The Inquisit script we use is tested to run perfectly with the LPT-based changer, so it could not be a script problem.
After some tests we discovered, if we ran Inquisit to control the changer after we had controlled the device via the terminal software, it suddenly worked. So we assume the terminal software somehow establishes a communication with the virtual com port that later also works for Inquisit. However, before establishing this communication, there seems to be a problem for Windows and/or Inquisit. Whenever the USB-changer is unplugged and plugged in again or whenever Windows is restarted, the communication has to be reestablished via the terminal software again.

Although we have a perfectly working (and simple) workaround, we thought you might be interested in this problem. Maybe you can even fix this so Inquisit can establish a proper communication itself? We are happy about any feedback :)!

Best wishes,
Mattis

PS.: lmk if you need any more information about specifications or scripts we use etc.