RHD USB/FPGA Interface: Rhythm USB3

To facilitate the development of electrophysiology recording systems using the RHD series of microchips, Intan Technologies provides the following open-source USB/FPGA interface for developers. Designated Rhythm USB3, the interface consists of Verilog HDL code and a C++ API written for the commercially-available Opal Kelly XEM6310 USB interface module. Rhythm USB3 configures the Xilinx FPGA on the Opal Kelly module to communicate with up to 16 RHD chips (1024 channels) over SPI buses and to stream data from these chips to a host computer over a SuperSpeed USB 3.0 interface.

The Rhythm USB3 API supports multi-platform development under Windows, Mac, or Linux. All API software is written in C++ to facilitate rapid development. The Rhythm USB3 interface is used at the core of the RHD recording controller software, which offers a quick way to evaluate the performance and operation of RHD chips with a plug-and-play USB interface and open-source GUI software written in C++/Qt.


  • Open-source Verilog HDL code configures a Xilinx FPGA to communicate with multiple RHD amplifier chips
  • Verilog code is written for a commercially-available Opal Kelly XEM6310 module with integrated SuperSpeed USB 3.0 interface
  • Up to 1024 simultaneous amplifier channels supported at sample rates from 1 kS/s to 30 kS/s per channel
  • Open-source host computer C++ API for multi-platform support


  • Windows, Mac, or Linux-based electrophysiology signal acquisition systems
  • Rapid prototyping of Intan Technologies RHD-based products
  • Starting point for the development of custom interfaces to RHD chips
Opal Kelly XEM6310 module
Opal Kelly XEM6310 module used for the Rhythm USB3 interface. This device, along with the Rhythm USB3 Verilog/C++ code, allows up to 1024 channels from 16 RHD chips to be controlled and sampled by a host computer.

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