  The RFX-mod2 Nuclear Fusion experiment is an upgrade of RFX-mod, shutdown in
2016. Among the other improvements in the machine structure and diagnostics, a
larger number of electromagnetic probes (EMs) is foreseen to provide more
information about plasma instabilities and to allow an improved real-time
plasma control. An Analog to Digital Converter (ADC) architecture able to
provide at the same time both transient recording and real-time streaming, as
well as FPGA-based time integration of the inputs is foreseen in RFX-mod2.
Transient recording provides full speed data acquisition (up to 1 MSample/s) by
recording data in local memory and reading memory content after the plasma
discharge. Real-time streaming of sub-sampled data is required for active
control. The chosen technology is based on the XILINX Zynq architecture that
provides in the same chip a multi-core ARM processor tightly coupled to a FPGA.
  Time critical functions are carried out by the FPGA, such as the management
of the circular data buffer, low pass filtering for subsampling of the samples
to be streamed and digital integration. Other functions are carried out by the
processor, such as the management of the configuration setting, received via
TCP/IP or HTTP, the data readout of acquired samples in transient recording
buffers and network data streaming of data collected for active real-time
plasma control.
