Abstract
Electronic control units based on microprocessors have been standard in ZF automatic transmissions since 1982. Innovations such as load reduction in internal combustion engines by means of ignition retard, intelligent shift programs, and the Tiptronic system, have all made a vital contribution towards popularizing automatic transmissions. Further improvements in consumption, driveability, and shift quality are vitally important to increase the penetration of automatic transmissions in Europe. To achieve desirable levels of functionality in the electronics field, 32-bit high performance microprocessors are needed. The software is written in ANSI C. A realtime operating system is used.