Abstract: An ambulatory recording system for medical and especially diagnostic purposes is described having synchronized communication between two processors. The recorder features two processors which are of differing architectures—the first processor being a real time processor which handles the sampling function, the second processor being a non real time processor which handles the operating system function. The invention further includes a protocol for communication between the two processors which permits the two processors to have synchronized and reliable communication.

Abstract: An ambulatory recording system, for medical and especially diagnostic purposes, is described having a communication watchdog between two processors. The two processors may be of differing types. For example, the first processor may be real time processor ("RTP") which handles the sampling function, while the second processor may be a non real time processor ("NRTP") which handles the operating system function. This dual processor design permits relatively low power consumption for data recording (which is handled by the relatively lower power consuming RTP), while also providing a graphical user interface for user simple user operation (which is handled by the relatively higher power consuming NRTP). A communication watchdog between the two processors is provided to reset the device upon the detection of a processor failure or communication failure between the two processors.