Transmission and reception, I-bus (1-lead)
Transmission and reception, I-bus (1-lead) |
The green bus lead is grounded internally in each control module via a 4 kΩ resistor. To send a zero the control module pulls the bus voltage up towards 5V. Voltage differences to ground less than 2.2 V are interpreted as a one and differences higher than 2.2 V as a zero. Note that a long series of ones is the same as if no message is transmitted.
The diagnostic tool is connected via the CANdi box to the 1-lead I-bus.
The 1-lead I-bus has a transmission speed of 33 kbit/s.