A high throughput controller for a 256-channel cardiac potential overlapping system

Describes an embedded controller board for a data acquisition system used in biomedical research. The board is essentially a 32 Mbyte memory buffer, accessible from four ports in round-robin fashion. Special FPGA-based sequencers managed by a local microcontroller provide a throughput of 2.5 Mbyte/s per port and automatically perform all low-level acquisition tasks: initiating A/D conversions, transferring A/D data to a buffer (queue) in memory and then transmitting the data to a host computer. The controller is presently used in a cardiac potential mapping system where it enables simultaneous acquisition of 256 channels at 4000 Hz per channel at a resolution of 12 bits per sample.