A fitter is a computer with specializations to work in a car, such as compact size, low power consumption and some custom components. The actual computer hardware is usually based on standard PCs or mobile devices. Because they are computer based, they usually have many standard interfaces such as Bluetooth, USB and WiFi. The first carpenter was introduced by Clarion Co. on December 4, 1998, although onboard diagnostics have been used since the 1980s to accurately measure the amount of fuel entering the engine when carburetors became too complex. A challenge to installing a computer in a car is the power supply. The energy is supplied in the form of a nominal current of 12 V DC in cars or 24 V in some trucks. The actual voltage varies depending on whether the motor is on or off because the battery typically delivers less than 12V, while the generator provides more. There may be peaks, and at the time of ignition, the power supply drops. External DC / DC converters can help regulate voltages so they can be used.
Police cars often have mobile data terminals in the form of a mounted laptop swivel where the driver’s armrest would be. This can be used to record data and query networked databases. Microsoft developed Windows Embedded Automotive and used it with AutoPC, a carpenter brand developed jointly with Clarion. The system was released in 1998, and refers to the operating system itself as “Auto PC”. It was based on Windows CE 2.0. It evolved into “Windows CE for the automobile”. The platform was used for the first two generations of MyFord Touch while the third generation uses QNX from BlackBerry Limited. Tablets such as the Nexus 7 can be permanently installed (at the dashboard) or removable (a dock). It can be used to watch movies or listen to music, as well as for GPS navigation. It also has a Bluetooth for hands-free calling. Computers can be used to decode on-board diagnostic data (OBD) to a visual display. Many interfaces are based on ELM327 OBD interpreter ICs. STN1110 is also known to be used.