of the bus clock signal conductors 120 the clock frequency detection logic 235 receives one or more bus clock signals senses a frequency of the bus clock signal s and outputs an indication of the present frequency of operation of the digital signal bus 105 or a portion thereof to the termination logic module as the bus state information the adaptive digital signal bus termination apparatus 200 further includes one or more termination control bus input terminal s 240 associated with the termination logic module 225 the termination control bus input terminals 240 are to couple to a termination control bus 243 the input terminals 240 receive the bus state information or the bus termination command from a controller 115 at the driver end 135 of the digital signal bus 105 the bus state information and or termination impedance commands are transferred across the termination control bus 243 and are used by the termination logic module 225 to set a state of each termination switch 210 and a resistance value of each variable termination resistor 215 the adaptive digital signal bus termination apparatus 200 also includes a bus command decoder 250 coupled to the termination logic module 225 the bus command decoder 250 is also to be coupled to a portion of the digital signal bus 105 or to the entirety thereof the bus command decoder 250 receives bus state information one or more bus termination commands and or one or more termination resistor calibration commands the bus state information and or commands are transmitted across the digital.