A medical device comprises a control system, processing modules, and a wire bundle connecting the control system to the processing modules, the wire bundle comprising control lines and data lines. Each processing module is coupled to a respective set of sensors arranged to interface with a biological tissue site, the sensors being configured to capture analog physiological signals generated from the biological tissue site. The control system is configured to generate a control signal on the control lines to initiate a data collection cycle by the processing modules. In response to the control signal, each processing module is configured to perform a respective data collection process which comprises (i) capturing and processing an analog physiological signal on each enabled sensor to generate a data sample for each analog physiological signal captured on each enabled sensor, and (ii) outputting data samples to the control system on the data lines.