Millisecond accurate USB TTL event marking module key features
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It doesn't matter which experiment generator you use to run your computer-based psychology experiments the Black Box ToolKit USB TTL Module helps you achieve millisecond accurate event marking/triggering across up to 16 I/O lines*

Designed as a parallel port replacement for simple event marking. Plug into a USB port on your PC/Mac/Linux system and our USB TTL Module will appear as a Virtual Com Port (VCP). To event mark send two hex bytes from your experiment generator. Quickly and easily event mark with any experiment generator via standard one line serial commands, e.g. task events in E-Prime. Works out of the box with E-Prime, SuperLab, Presentation, Inquisit, PsychoPy or any other software that can read and write to a standard serial port.

When triggering from MRI, EEG, ERP, MEG systems wait for a sync pulse that has been converted to two incoming hex bytes. Think of the module as a USB to TTL adapter or TTL to USB interface.

All USB TTL modules ship with a USB host lead. An optional breakout board enables you to wire your own cables before making them permanent.

Key features TTL breakout board Pinouts Technical specifications Pricing Config software  
Key features
  • 16 Digital +5V TTL Lines
    • 8 TTL Input
    • 8 TTL Output
  • TTL Input Lines configured as an 8 bit port
  • TTL Output Lines configured as an 8 bit port
  • Change detection on TTL Input lines
  • TTL Input to 2 hex bytes conversion representing 255 possible states
  • Event marking: 2 hex bytes to TTL Output across 8 bit port representing 255 possible states
  • TTL Output lines automatically latch once set
  • Works out of the box with PCs/Macs/Linux – fully plug in & play
  • Appears as a Virtual Com Port (VCP)
  • Compatible with all Psychology experiment generators, e.g. E-Prime, SuperLab, Presentation, Inquisit, DMDX, ERTS, DirectRT, PsyScope, PsychoPy, OpenSesame etc.
  • Works with any software that can access a standard serial port
  • Comes complete with timing validation software
  • Fully documented API complete with examples
  • Small and unobtrusive – Dimensions: 67.1mm x 28.2mm x 67.1mm (WHD)
  • LED indicators for Input (green) and Output (red)
  • Full-speed USB 2.0 (compatible with USB 3.0)
  • Scans for TTL I/O changes 109,000 times each second
  • Guarantee millisecond accurate TTL event marking*


Example usage
Using the BBTK USB TLL event marking module is easy. Simply open a standard serial port and send two hex bytes to event mark. In the examples shown below for PsychoPy, E-Prime and MATLAB the module event marks on TTL Out Line 1 (01) immediately prior to a stimulus image being displayed. Once the stimulus terminates all TTL lines are cleared with 00.

PsychoPy E-Prime MATLAB
import serial
ser = serial.Serial(0, 115200, timeout=1)
<My Stimulus Image Shown Here>
Serial.WriteString "01"
<My Stimulus Image Shown Here>
Serial.WriteString "00"
s = serial('COM1');
set(s, 'BaudRate', 115200, 'DataBits', 8, 'StopBits', 1, 'Parity', 'none');
fprintf(s, '01');
<My Stimulus Image Shown Here>
fprintf(s, '00');

*Remember although our USB TTL event marking modules are millisecond accurate they can't automatically correct for any mistimings that are inherent within the experiment generator you use.

Unless otherwise labelled, all products offered for sale by The Black Box ToolKit Ltd are for academic study and/or research use only.