
RFSoC Data Converter Evaluation Tool User Guide
15
UG1287 (v2018.2) October 1, 2018
Chapter 3:
Hardware Design
The design is configured to operate in 8x8 mode (8-channel RF-DAC and 8-channel
RF-ADC). The RFDC datapath consists of AXI DMA and Stream Pipe IPs for high performance
data transfers between PS/PL DDR memories and RFDC IP. The RFDC datapath is based on
AMBA AXI4-Stream protocol and the control path is based on the AXI4-Lite interface. Both
datapath and control paths are implemented in the PL.
The PS is configured with a GEM Ethernet controller (GEM3) and I2C controllers (I2C0 and
I2C1). The GEM Ethernet controller enables a Gigabit Ethernet interface between the host
machine and the ZCU111 board. The I2C controller provides an interface between the PS
and the on-board RF PLLs.
The
SD card
holds the image and file system, which loads the FPGA part when power is
switched on.
The information passed from the host system GUI via Ethernet to the ZCU11 platform is
stored in the PL DDR using a
DDR controller
. The application running on the processor then
transfers this data to the programmable logic over the AXI ports.
The following sections provide detailed information for both RF-DAC and RF-ADC
datapaths.
DAC Data Flow
shows the datapath implementation for the 8-channel RF-DAC (RF-DAC0 and
RF-DAC7). There are eight stream pipes implemented.
Each of these stream pipes feed data to
the RF-DAC. Due to the extreme speed of the RF-DAC, it is not possible to live-feed the data
using Ethernet, hence user-selected signals are continuously looped over or replayed to create
a continuous and measurable signal at the output o
f the DAC.
There are two ways input samples are stored and replayed:
• Samples are stored and looped over in PL DDR (high storage but reduced speed).
• Samples are stored and looped over in block RAM (low storage but highest speed).