ALDL COMMODORE SOFTWARE LIBRARY SERIAL
ALDL COMMODORE SOFTWARE LIBRARY CODE

ECU code along with engine specific data such as fuel maps are hard coded into a removable EPROM chip inside the ECU, which is called the вЂњMemCalвЂќ, which stands for Memory Calibration Unit. The code mask used in this project is $8d, which is used on the 1990-1992 Pontiac Firebird, 1990-1992 Chevrolet Camaro, and the 1990-1991 Chevrolet Corvette. The specific code mask a vehicle runs is determined by engine type, transmission configuration, which ECU is used in the vehicle, and other vehicle features. GM has platform dependent code which is vehicle specific and is called code вЂњmasksвЂќ. This code has since been disassembled and commented by auto hobbyists for the general public use.

The processor runs at 8.388 MhzвЂ™s, has 2 kilobytes of RAM, and a 32 kilobyte UV EPROM for code and calibration data. The ECU has a customized version of the Motorola 6811 processor and runs code written in Assembly. The ECU chosen for this project is one found is many late 1980вЂ™s and early 1990вЂ™s GM vehicles and is know by its part number, 1227730 (or 1227727 which is the under hood version).

The OBD-I interface on GM cars is a proprietary GM interface. GM started using the 8192 baud OBD-I interface in 1986 and continued using it widely until 1995 when a universal interface and protocol was mandated by SAE (OBD-II). This diagnostic data is then processed by the AVR microcontroller and outputted to a LCD in an easy to read format for the user to view.ДЎ.4 Background on Project: This project will focus on interfacing with an onboard automotive computer using the GM later 8192 baud OBD-I interface.

ALDL COMMODORE SOFTWARE LIBRARY SERIAL

This interface utilizes an Atmel AVR 8-bit microcontroller to perform serial communication over a one wire serial interface with the ECU. The hardware, software, and interface details are described.ДЎ.3 Project Overview: In this project an interface and display was designed to retrieve automotive diagnostic data from a late 1980вЂ™s to early 1990вЂ™s General Motors automotive engine control unit / computer known as an ECU. This information is then processed and output to a LCD. The device utilizes a propriety serial interface to connect to an automotive engine control computer and retrieve current engine conditions. 1.2 Abstract: A microcontroller based automotive computer interface is described. That is also why you will see two distinct writing styles, the more formal style used in the report and my more laid back personal how-to style of the added information sections. Much of this information was written in a formal technical writing manor, I have since gone back and added some for more in-depth information others might find useful who have more background knowledge on GM engine control systems then my professor who read the report at the time. I have copied and pasted a lot of the description out of the project formal report. Project Overview 1.1 Heads-up: This project was done for my 2007 Senor design project class in college. Project status: Project Completed Project first started: February 2007 Project finished: Late April 2007 Project Scope: 2007 Senior Design Engineering Project Old Dominion University GM OBD-I ALDL Atmel AVR LCD interface pulling data off a 7730 $8D ECU 1. An ALDL cable is an OBD1 diagnostic scantool suitable for diagnosing engine fault codes and live engine data found in VR-VY Holden Commodores! The вЂlanguageвЂ™ spoken is called ALDL (Assembly Line Diagnostic Link), it is a very unique protocol that General Motors implemented on our commodores.

Aldl commodore software library