or micro control unit mcu 200 in direct communication with one or more sensors 202 i e without using the signaling or service bus of circuit board 10 one or more sensors 202 may include an accelerometer 210 humidity sensor 212 temperature sensor 214 other sensors may include a gyroscope airflow sensor enclosure intrusion sensor and the like sensor board 50 may also include various sensor specific circuitry or chips to provide analog to digital conversion adc sampling circuit protection buffering etc sensor board 50 may also include volatile and or persistent memory 220 in communication with mcu 200 a connector 60 is provided to removably secure sensor board 50 to a main circuit board and may be implemented by a standard board to board connector in one embodiment connector 60 is implemented by a surface mount compatible dual row vertical connector with a polarizing peg and provides up to 15 w of power sensor board 50 may also be hard wired or soldered to circuit board 10 for some applications as shown in fig1 and 2 a system or method for monitoring operating conditions of a main circuit board 10 having a processor 20 and an associated signaling or service bus include a controller 200 in direct communication with at least one sensor 202 without using the signaling bus sensor board 50 or controller 200 is assigned a single unique address on the signaling or service.