Craig E. Steiner Reverse Engineering Project "Reverse engineered 8052 firmware and wrote new assembly language version" Back to full resume | PDF version of this page Overview Project consisted of reverse engineering an existing 8052 assembly language program, determining the use and function of each of 32 digital I/O lines, and writing a new assembly language version of the software. The task was made more complicated due to the fact that the original firmware interacted with external devices and such interaction had to be identical to the original, such that components and the user couldn't detect the difference. The final product was a control panel that is currently being sold in quantity to the U.S. Postal Service as one of the principal components of mail sorting machines. Approach Reverse engineered the original firmware and produced an assembly language original version. Determined functionality of original version based on the assembly language that I had reverse engineered. Wrote entirely new version of the firmware in assembly language referencing only the functionality that had been determined and intentionally ignoring the actual assembly language of the original firmware. External components that were driven by the firmware include tough buttons, lights, 4 LCDs, and the exchange of information to an attached PC via the RS-232 port. Project also required the reverse engineering of the proprietary protocol. Technology Used 8052 Simulator to perform initial disassembly and reverse engineering of the original firmware. Manually determined the purpose of each section of disassembled code to determine its function. Wrote new code in assembly language using Archimedes assembler. Craig Steiner's Role Sole reverse engineer of the original firmware. Sole designer and developer for the new version of the firmware. Contact Project Customer/Reference    Paul Calixto Link World Trade (now USA Signal, Inc.) 15167 Business Ave Addison, TX 75001 Phone: 469-522-0820 Email: (Available upon request) Contact Craig Steiner Vault Information Services 8174 S. Holly PMB #272 Littleton, CO 80122 Phone: 303-439-0909 Email: csteiner@vaultbbs.com (C) Copyright 1997 - 2008 by Vault Information Services LLC. All Rights Reserved. Information provided "as-is" without warranty. Please see details. Contact us for usage and copy permission.