CROSSBAR LAN TEAM 8 CURTIS PETE D. ERIC ANDERSON DANIEL HYINK JOHN MUFARRIGE

Overview Network connection using a 4 x 4 crossbar implemented on FPGA Interface to crossbar using 3 National Instruments DIO32 cards and 1 National Instruments DIO96 card Cards are controlled using C programming and LabVIEW virtual instruments

Hardware Issues Had to wire a new FPGA board for our data communications.

Hardware Issues Problems implementing FIFOs onto FPGA –ground loop was discovered between DI/O ground and serial port ground of PC causing bad FPGA programming –clocks used to latch data required debouncers to work properly

Project Achievements Establish a bi-directional connection of 2 workstations using NI DIO-32HS PCI interface cards. Using a parallel 8-bit wide interface LabVIEW and C were used to control I/O cards

C Software Achievements Initially used software implemented handshaking to control the cards

C Software Achievements Data I/O cards were connected directly to each other

C Software Achievements Next, the cards were connected through FIFOs

C Software Achievements Data was latched into/out of FIFOs using external asynchronous clocks

C Software Achievements Data packeting was introduced into the software

C Software Achievements Final software uses a command line interface to perform tasks

LabVIEW Achievements Used as an alternative to C for driving data among PC’s. LabVIEW was supposed to be simpler to program and provide similar performance to C. Built input and output programs to send and receive data between 2 PCs

Input Program Front Panel

Output Front Panel with Timing

LabVIEW Timing Results Speed was calculated by dividing the number of bytes sent by the elapsed time.

C Software Timing Results

Conclusion The interface to the crossbar is complete. –The software works independently of whether or not there is a crossbar implemented between the FIFOs. From our timing data, we can conclude that LabVIEW is not a feasible solution for controlling the DI/O cards.