Zynq Architecture
Understand the split between the Processing System and programmable logic in Zynq-7000 and Zynq UltraScale+ MPSoC devices.
A processor and an FPGA in one device
A Zynq is a system on chip, or SoC. It combines a complete processor system and an FPGA fabric in one component. AMD calls these two parts the Processing System, or PS, and the Programmable Logic, or PL.
The PS contains ARM processors, memory controllers and peripherals. It runs software written in C or C++. The PL contains LUTs, flip-flops, block memories and DSP blocks. A LUT implements a small logic function. A flip-flop stores one bit on a clock edge. A DSP block performs arithmetic operations efficiently. Together, these resources implement circuits described in VHDL or Verilog.
This split guides the engineering work. Software handles decisions, complex protocols and the operating system. Programmable logic handles parallel data flows, custom interfaces and functions that need predictable latency.
The Zynq-7000 family
Zynq-7000 combines one or two ARM Cortex-A9 cores with a 7 series FPGA fabric. The PS contains the following resources.
| Resource | Function |
|---|---|
| APU | Runs the application and can host an operating system |
| L1 and L2 caches | Reduce the average access time for instructions and data |
| OCM | Provides 256 KiB of fast internal memory |
| DDR controller | Connects the PS to external dynamic memory |
| GIC | Prioritizes and distributes interrupts |
| PS DMA | Moves data without making the processor copy every word |
| MIO and EMIO | Connect PS peripherals to pins or to the PL |
Integrated peripherals include UART, SPI, I2C, CAN, USB, Ethernet, GPIO and SDIO. These hard peripherals avoid rebuilding standard functions in the PL.
The PL provides the hardware resources. It can implement a processing pipeline, a custom controller, an accelerator or an AXI peripheral. The PS and PL communicate mainly through AXI interfaces.
The Zynq UltraScale+ MPSoC family
Zynq UltraScale+ MPSoC keeps the PS and PL split but provides a more capable PS.
| Block | Main function |
|---|---|