J1850-Bus

The J1850 bus is a field bus standardized by the Society of Automotive Engineers( SAE) for heavy-duty trucks, which is mainly used in North America but has been superseded by the CAN bus.

The J1850 bus is a low-cost, open architecture in bus topology without a master station. The J1850 standard supports two different methods: Pulse Width Modulation( PWM) with a data rate of 41.6 kbit/s and Variable Pulse Width( VPW) with 10.4 kbit/s. It defines the arbitration and the data frame of J1850, as well as the character sets, the physical layer and the response time behavior.