Multiple-mode data acquisition system

A multiple-mode system for acquisition of data over a plurality of channels from a plurality of sources, comprising:

• switching means having a plurality of addressable input ports including a first input port for receiving a low reference potential, a second input port for receiving a high reference potential, and an output port, for connecting input signals occurring at selectively addressed ones of said input ports to said output port, a first plurality of said input ports being coupled to receive local signals having a voltage amplitude indicative of acquired data, and a second plurality of said input ports being coupled to receive input signals within a first frequency band and having a frequency indicative of acquired data;
• first converter means for changing said local signals from said output port into a first plurality of variable signals within a second frequency band when said output port is connected to said input ports, said variable signals within said second frequency band exhibiting frequencies proportional to the voltage amplitude of said local signals occurring at said input ports;
• second converter means receptively coupled to said first converter means and said switching means for selectively changing said first plurality of variable signals within said second frequency band and said input signals within said first frequency band into digital signals;
• first processing means operatively connected between said second converter means and said switching means during a first mode, for performing an internal failure detection routine, for sequentially addressing said first and second plurality of input ports to selectively couple said input ports to said output port, for controlling conversion of said first plurality of variable signals within said second frequency band and said input signals within said first frequency band by said second converter means for storing and processing said digital signals, and for encoding said digital signals as variable signals within said second frequency band by addressing alternate ones of said first and second input ports in correspondence to the relative instantaeous amplitudes of said digital signals;
• transmitter means periodically enabled by said first processing means during said first mode and coupled to said first plurality of variable signals from said first converter means for transmitting said variable signals within said second frequency band while enabled;
• and
• means for enabling said first processing means during said first mode and for enabling said transmitter means during a second mode;
• means for monitoring said internal failure detection routine and for generating a mode-shifting signal initiating said second mode in response to detection of an internal failure by said detection routine;
• and
• addressing means enabled by said mode-shifting signal for sequentially addressing said input ports during said second mode to selectively couple said first and second plurality of input ports to said output port.

A multiple-mode process for acquiring data over a plurality of channels from a plurality of sources, comprising:

• connecting a first plurality of channels emitting input signals exhibiting a first signal format to a first plurality of input ports of a switchable device;
• coupling a second plurality of channels emitting input signals within a first frequency band to a second plurality of input ports of said switchable device;
• operating said switchable device to sequentially couple said first and second pluralities of input ports to an output port;
• serially converting said signals exhibiting said first signal format at said output port into a first plurality of variable signals within a second frequency band, said first plurality of variable signals exhibiting frequencies proportional to the values of data represented by said input signals exhibiting said first signal format;
• sequentially converting said first plurality of variable signals within said second frequency band and said input signals within said first frequency band into digital signals;
• processing and storing said digital signals;
• coupling a first and a second input port of said switchable means to receive a low and a high reference potential;
• applying said digital signals to address and couple said first input port and said second input port to said output port in correspondence to the instantaneous value of said digital signals;
• converting the analog values of said low and high reference potentials occurring at said output port into variable frequencies proportional to the instantaneous amplitudes of said analog values;
• and
• transmitting said first plurality of variable frequencies within said second frequency band to a distantly located receiver.