NI USB-6501 TTL Adapter

6 parameters · DB-25 / USB · 24 digital I/O

Overview

The NI USB-6501 TTL Adapter interfaces ConductMaze with National Instruments USB-6501 digital I/O devices, providing 24 individually addressable digital lines. This enables maximum channel separation — each behavioral event type can have its own dedicated digital line, eliminating the need for post-hoc event parsing.

The USB-6501 is widely used in neuroscience labs as a general-purpose digital interface between behavioral control software and recording systems. The ConductMaze adapter handles the NI-DAQmx API communication automatically, requiring no LabVIEW or custom scripting.

Setup Instructions

  1. Install NI-DAQmx runtime from the National Instruments website.
  2. Connect the NI USB-6501 to your computer via USB. Verify it appears in NI MAX as "Dev1" (or similar).
  3. In ConductMaze > Integrations > NI USB-6501, enter the device name from NI MAX.
  4. Select the port (Port0 = lines 0-7, Port1 = lines 8-15, Port2 = lines 16-23) and line mapping.
  5. Wire the DB-25 connector or individual screw terminals to your recording system digital inputs.
  6. Run a test: trigger each event type and verify the correct digital line activates on your recording system.

Common Pitfalls

  • The NI USB-6501 outputs 3.3V logic levels (not 5V). If your recording system requires 5V TTL, add a level shifter between the USB-6501 output and the recording input.
  • NI-DAQmx runtime must be installed even though ConductMaze handles the API calls. Without it, the adapter will fail silently.
  • USB-6501 has 3 ports of 8 lines each (24 total). For protocols with more than 8 event types, enable multi-port mode to span across ports.
  • The DB-25 connector pinout varies by breakout board manufacturer. Verify pin-to-line mapping with NI MAX Test Panels before connecting to expensive recording equipment.

Methods Text (Copy-Paste)

Behavioral events were digitized using a National Instruments USB-6501 digital I/O device (National Instruments, Austin, TX) controlled by the ConductMaze NI Adapter (ConductScience, Skokie, IL). Each event type was mapped to a dedicated digital output line (3.3V, 100ms pulse) on the 24-line USB-6501, providing unambiguous event identification without post-hoc parsing.

Suggested text for the Methods section of your manuscript.

Parameters

ParameterTypeDefaultDescription
NI Device NamestringDev1NI-DAQmx device identifier (from NI MAX)
Port AssignmentenumPort0NI port for event output (Port0, Port1, Port2)
Line MappingenumAutoAutomatic (sequential) or custom line-to-event mapping
Output ModeenumPulsePulse (brief high) or Latch (stay high until next event)
Pulse Durationinteger100Pulse width in milliseconds (for Pulse mode)
NI-DAQmx Versionenum2024 Q1Required NI-DAQmx runtime version

Compatible Products

ME-OC-TTL

Ready to Automate Your Behavioral Protocols?

Contact us for a demo and pricing information.