Shreedutt C. Hegde
Hardware and FPGA system design  

​Description:

• Involved setting up a wireless link between a PC, and a brain implant PCB designed for epilepsy detection and termination.

• Developed a custom firmware, in C language, for the USB dongle plugged to a PC, wrote Verilog code for the FPGA that controlled the RFIC on brain implant PCB, and MATLAB script for real-time plot of recorded brain signals.

Takeaways:

• Implementing SPI protocol in Verilog for FPGA to communicate with SPI-compliant RFIC.

• Working with USB 2.0 CDC class libraries, MRFI API(data link layer software by TI) and knowledge of code organization.

• Extensive handling of test instruments :oscilloscopes, logic analyzer, and signal generators, to perform systematic debugging.

• Experience of working in multicultural team environment.

Challenges solved:

• Maximized overall system throughput and minimized packet loss by handling bottleneck created by RFIC data rate limitation, through implementation of FIFO buffers after an in-depth signal timing analysis.

Impact and significance:

• The implant PCB is now capable of transmitting the recorded neural data, wirelessly to the dongle, and graph it in real time on MATLAB.

• The default firmware on USB dongle allows it to only receive data. However my new modified firmware allows the dongle to receive as well as send data from PC back to implant PCB, as a COM port device, allowing for a closed-loop neural recording and stimulation system.