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Class 2 Serial Data Line

Class 2 serial data is transmitted on single wire at an average of 10.4 Kbps (10,400 bits per second). This is only an average because Class 2 uses a Variable Pulse Width modulation to carry data, and depending on the message, it may operate faster or slower. The bus is active at 7.0V nominal and inactive at ground potential. The Class 2 serial data line is tolerant, however, to different levels of ground potential.