Portable auto diagnostic tools for receiving information from an automotive computer of a vehicle. The portable auto diagnostic tools is battery powered. The portable auto diagnostic tools comprises a microcontroller, a display, a keypad, a flash memory, a SRAM, a battery backup circuit, a ROM, a UART, and a port. Automotive codes for configuring the portable auto diagnostic tools are stored in flash memory. The automotive codes are compressed to increase storage to the flash memory. The flash memory is non-volatile and retains the automotive codes when power is removed. The automotive codes are updated by writing new automotive codes to the flash memory. Information or data received from an automotive computer is stored in SRAM. The battery backup circuit powers the SRAM to maintain the information to be taken to a different location when the power is turned off.
This invention relates, in general, to auto diagnostic toolss, and more particularly, to an auto diagnostic tools which receives information from an automotive computer of an automobile.
The automobile has played an important role in increasing the range in which a human is able to travel on a daily basis. In fact, the automobile has permeated our society to the extent that we have become reliant on the automobile for our transportation needs. The automobile became an indispensable part of daily life when its price was reduced to an affordable level for the average working man and woman. Still, the purchase of an automobile is not a trivial issue, other than the purchase of a home, it is typically the next most expensive purchase made.
In the past, maintaining and repairing an automobile was a popular way to reduce the cost of owning an automobile. The mechanical nature of the automobile allowed one to understand its operation without significant special training. This is no longer true in a modern automobile even though the principles of operation are still the same. The increased complexity of the automobile resides in the addition of electronics to control every facet of automobile operation. The use of microprocessors and sensor technology throughout a car has allowed much finer control of its operation thus allowing today's automobile to provide more power with greater fuel efficiency while reducing the amount of toxic emissions. The addition of electronics has also discouraged most people from maintenance and repair because the electronics must be interfaced to diagnose a problem. The equipment used by professional automotive technicians to interface with the electronics of an automobile is cost prohibitive (typically greater than one thousand dollars) for someone wanting to tune-up or make minor repairs on one or two vehicles. Moreover, the average person is intimidated because he or she has little or no knowledge on how electrical devices operate (such as a microprocessor) or how the electronic system controls the automobile.
The integration of semiconductor devices within an automobile has mirrored the development and advancements of the semiconductor industry. Electronics have permeated every facet of the automobile, from fuel pumps to engine control. Microcontrollers are used extensively throughout an automobile to more efficiently operate all mechanical functions. No better example of this technical sophistication is the engine management system of an automobile. The engine computer rapidly senses engine parameters via sensors such as exhaust, air intake, fuel, temperature etc. and makes adjustments to minimize exhaust pollution, minimize fuel consumption, and maximize engine power. The results have been dramatic, today's automobile provides far more luxury, reliability, efficiency, and safety than its brethren of just a few years ago.
An automotive microcontroller is also used as a diagnostic tool for indicating problems. Data from sensors used on the automobile provide information that is stored by a microcontroller when an event occurs which is outside normal operating parameters. Also, the microcontroller can be used to take a "snapshot" of the output of each sensor at a particular point in time while an automobile is operating. In general, the microcontrollers are programmed to identify problems and to output data which would indicate a course of action in the repair of an automobile. The information stored on the microcontroller is ported out for analysis. For example, information from an engine management system is downloaded for providing data on the spark, fuel, air intake, or exhaust of an automobile. The information is used to determine if the engine is operating correctly. The automotive microcontroller can also be programmed to recognize specific faults based on the operating information. The identified fault is stored in memory as a fault code which can be received with the operating information to help diagnose a problem. Information on fault codes are typically written in a service manual for an automobile. A service manual defines each fault code and suggests potential sources for each problem associated with a fault code which greatly aids in the diagnosis of a problem.
auto diagnostic toolss currently offered in the marketplace for interfacing with an automotive computer are tailored for the professional auto mechanic. In general, an auto diagnostic tools is designed to be a permanent piece of hardware in an automobile repair facility. Most auto diagnostic tools are not truly portable, for example, some are built on a cart for easy mobility and for providing a large readout screen but cannot easily be carried from location to location. An auto diagnostic tools also is typically powered from a standard AC wall outlet since they are used on a continuous basis. The mobility is thus limited to the length of the power cord.
A typical auto mechanic works on a wide variety of automobiles. An auto diagnostic tools for the professional mechanic must have the capability of interfacing with each type of automotive computer used by automobile manufacturers to provide full service.
An example of a typical usage of portable auto diagnostic tools best illustrates advantages over prior art diagnostic tools. Automotive codings are compressed and loaded into flash memory during manufacture. Portable auto diagnostic tools can be shelved indefinitely at a store without losing the automotive codings due to the non-volatile characteristic of flash memory 34 thus a store owner will never have obsolete inventory. New automotive codings can be written to flash memory via port without purchasing additional components or sending the unit to the manufacturing facility.