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ALQ155 AAG Conversion Clinic. Team Members David Gedge Nate Decker William Sackett Spencer Little Advisors Dr. Priyank Kalla Thomas Dixon Special Thanks to Craig Gordon, Tim Price, and Ryan Yoshida. ALQ155 AAG Clinic 2008. 1. Recap on the HAFB Clinic.
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ALQ155 AAG Clinic 2008 ALQ155 AAG Conversion Clinic Team Members David Gedge Nate Decker William Sackett Spencer Little Advisors Dr. Priyank Kalla Thomas Dixon Special Thanks to Craig Gordon, Tim Price, and Ryan Yoshida ALQ155 AAG Clinic 2008 1
Recap on the HAFB Clinic Military aircraft use Line Replaceable Units (LRU’s) ALQ155 AAG Clinic 2008
CAPRE The airforce uses a program on a laptop called CAPRE to communicate with and configure LRU’s on planes. ALQ155 AAG Clinic 2008
PIM PAM The Big Picture To adapt to newer technologies, older tools are being upgraded. LRU ALQ155 AAG Clinic 2008
Programmable Interface Module • The PIM 2.0 is our focus • PIM hardware has changed from 1.1 to 2.0 • New FPGA • New USB chip • New peripherals ALQ155 AAG Clinic 2008
ALQ155 AAG Clinic 2008 How does that affect us? • To address these changes, we altered: • USB Firmware • CAPRE Software • FPGA Bitmap
ALQ155 AAG Clinic 2008 FPGA • The PIM is talks to several different LRU’s • To facilitate this, the core is an FPGA • -Xilinx Spartan3 • The FPGA executes a bitmap generated through VHDL by Xilinx ISE
ALQ155 AAG Clinic 2008 Creating the Bitmap • Pre-existing VHDL code was available from past clinics • FPGA pinout for the Spartan3 had changed • A new user constraint file (UCF) was needed • Using the schematics from both the older and newer PIM designs the older UCF was translated into the new file
An Extra Step • Default bitmaps created by the Xilinx bitgen are the wrong format for loading onto the FPGA • We correct this using a Xilinx tool called PromGen ALQ155 AAG Clinic 2008
Disable unused peripherals • We do not need to use • RAM • RS232 • 1553 • Each device is disabled with a control signal. ALQ155 AAG Clinic 2008
ALQ155 AAG Clinic 2008 New VHDL Signals
ALQ155 AAG Clinic 2008 Problem: Power Failure • Problem: • After loading the FPGA, the USB chip would sometimes lose its data • Cause: • A bank of capacitors was drawing power • Solution: • Introduce delays into the power-up sequence
ALQ155 AAG Clinic 2008 Capacitor Banks
VHDL Power-up Delays A counter is used to delay each enable signal leading to each bank of capacitors Pswitch: 11110111,11100111,11000111,10000111 ALQ155 AAG Clinic 2008
ALQ155 AAG Clinic 2008 The Result • Error message: LRU is not responding
ALQ155 AAG Clinic 2008 Feedback • Questions or Comments?