Problems Encountered - Up to Midterm State Machine Transitions Much Too Fast - Solved by Decreasing Clock (LED Circuit) Difficult to Test LED (Column) Display Without Proper Band Filtering NS16550 UART (Communications IC) Becomes Extremely Hot Serial Communication More Difficult to Implement than Previously Expected

Other Problems Encountered…since Midterm LCD – Idea abandoned after a week and a half of trying to get it to work Needed more external hardware to fully implement it – OEM Version  Used for showing the band and its current dB level  Not Imperative – mostly for eye candy

Problems cont… Alternate Solution? Added another seven segment LED to show which band user is on (1-5) Band’s current dB level displayed on the PC using the VB software Hmmm…another problem? – No PC? Would need to add some type of external memory element to store previous dB level – Future Group?

Problems cont… Main Equalizer IC problems: IC packaging not normal (legs closer together than regular TTL ICs Hence…made a modification – Seen in Lab Bought (2): One does not work at all Other one – through wear and tear, the input (audio signal in) leg broken off Hence, No Testing Waiting on New One to Arrive – On Order All testing done using the Xilinx Simulator

What could be improved, perhaps next group? Knowing what we know now, add a LCD component to display bands Or add some type of memory element to store dB levels Add battery to FPGA to store instructions (when powered off) – also makes it portable (Stereo Use) Maybe a different UART? Makes communication easier

New (Approximate) Cost of Prototype 50 LEDs ~ $15-$20 Miscellaneous Driver Chips for seven segment/columnar LEDs (7) ~ $15 FPGA Chip ~ (We think) $15 Misc. Wires, Buttons, Capacitors, Resistors ~ $20 Xilinx Software (FPGA) - ?

Costs cont… UART IC ~ $10 Equalizer IC ~ $12-20 (If Available) Total ~ <$100 w/out Cost of Software Included…… …Conclusion……much cheaper than originally thought

Andrew Nguyen’s Contributions Fabricate the Hardware Build State Machine for the Equalizer Build the Circuit for the Equalizer Test the Equalizer Help Craig and Kevin

Craig Petersen’s Contribution Developed Both a Hardware and FPGA Version of LED (Digital) Display (State Machine) - Displays Band, dB Level, Positive/Negative Sign, and decimal point Developed LED (Column) Display Using 10 LEDs for Each Band Helping Andrew Communicate with Equalizer Circuit - State Machine and Verilog Code for I 2 C Bus

Kevin Wong’s Contribution Worked On Equalizer Control Software (PC - Visual Basic) Wired-Up Stand-Alone FPGA Built The Serial Interface Circuit Implemented UART Control State Machine Also helped Andrew and Craig

Nguyen Nguyen’s Contributions Write code in Visual Basic to test on a loop-back cable. Help around in making circuit board layout. Figure out the pin number on Xilinx chip to connect to RS-232. Using state machine to change the state of output frequencies.

In Summary… 95 % Complete…Should be completely ready by demo time later this week. Good experience in software and hardware integration Learned to work as a Team to complete an objective