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Sundance SMT784 v.1.0 User Manual

Page 18

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Version 1.0

Page 18 of 31

SMT784 User Manual

ADC Data Flow

The flow of ADC data in the SMT784:

Figure 5 ADC Data Flow

The Control Registers contained in the FPGA (control_SMT384) control the complete
functionality of the SMT384. Registers are written to/from the PC via the X-Link
interface (Comport). Contents of the registers or samples from the ADC’s can be
read back from the FPGA by choosing which output is desired. By changing the
default firmware, samples from the ADC’s can optionally be routed to the RSL links,
SHB, SATA, etc.

Details of the registers functions, word format and a memory-map of the FPGA can
be found in the

SMT384 User Guide

.

Serial control signals are routed from the registers to the ADC’s and to the clock
distribution system for desired configuration. Samples and the clock output from the
ADC’s are then combined onto two different 32-bit buses, one containing samples
from channels A and B, the other bus containing samples from channels C and D. In
order to prevent loss of data, an asynchronous 16K buffer is implemented to feed the