ZYNQ is a new generation of fully programmable system on chip (APSoC) launched by Xilinx. It perfectly integrates the software programmability of the processor and the hardware programmability of FPGA to provide unparalleled system performance and flexibility. And scalability. Different from traditional SoC solutions, highly flexible programmable logic (FPGA) can achieve system optimization and differentiation, allowing the addition of custom peripherals and accelerators to adapt to a wide range of applications.
The Zynq-7000 series is the industry's first scalable processing platform launched by Xilinx in April 2010. It is designed to provide the required processing power and computing performance for high-end embedded applications such as video surveillance, car driver assistance, and factory automation. This ARM processor-based SoC can meet the requirements of high performance, low power consumption and multi-core processing capabilities of complex embedded systems.
The essential feature of ZYNQ is that it combines a dual-core ARM Cortex-A9 processor and a traditional Field Programmable Gate Array (FPGA) logic component. Since the programmable logic part of this new device is based on Xilinx’s 7 series FPGA of 28nm process, “7000” has been added to the name of this series of products to maintain consistency with the 7 series FPGA, and it will also facilitate future new series of this series. The naming of the product.
The full name of ZYNQ is Zynq-7000 All Programmable SoC, that is to say, ZYNQ is actually a System on
Chip (System on Chip, SoC). So, what is "SoC"?
A circuit system that can realize a certain function is composed of multiple modules, such as a processor, an interface, a memory, an analog-to-digital converter, and so on. These functional modules can be implemented by discrete devices, and then combined on a printed circuit board (PCB) to form a system-on-a-board (System-on-a-Board). The schematic diagram of the on-board system is as follows:
In the on-board system shown in the figure above, the green rectangle represents the printed circuit board (PCB), and the small rectangles in various colors above represent the various functional modules in the system, such as memory. The functions of these modules are realized by independent silicon chips, and they are connected by metal traces on the PCB to form a complete system.
System-on-Chip refers to the functions of the entire system that can be realized on a single silicon chip. The schematic diagram is as follows:
As shown in the figure above, the system-on-chip (SoC) realizes storage, processing, and Various functional modules such as logic and interfaces, rather than the on-board system, need to be implemented with several different physical chips. Compared with on-board systems, SoC solutions cost less, can achieve faster and safer data transmission between different system units, have higher overall system speed, lower power consumption, and smaller physical Size and better reliability.
In the past, the term SoC was often used to refer to application specific integrated circuits （Application Specific Integrated Circuit，ASIC）. Representative examples of ASIC-based SoCs include processors used in PCs, tablets, and smart phones, such as the Kirin series chips in Huawei's flagship phones. These processors are typically composed of at least two processor cores, memories, graphics processors, interfaces, and other functional modules. There are two main disadvantages of ASIC-based SoC:
1. Long development cycle and huge cost;
2. Lack of flexibility.
The engineering investment that is not reusable when developing ASICs is huge, making this SoC type only suitable for high-volume and limited-life products.
The limitations of ASIC SoCs make them unsuitable for many applications, especially when the ability to quickly enter the market, flexibility and upgradeability have become important key factors. For low-volume or medium-volume products, ASIC SoC is not a good solution.
Programmable System-on-Progammable-Chip (SOPC, System-on-Progammable-Chip)Provides a more flexible solution for the above-mentioned applications: a SoC implemented on a programmable, reconfigurable chip. Among them, the programmable chip refers to FPGA. The inherent flexibility of FPGAs allows them to be reconfigured at will to achieve the functions of different systems, including embedded processors. Compared with using ASIC to realize SoC, FPGA can form a more basic and flexible platform, which is convenient for system upgrade.
Compared with SOPC, ZYNQ provides a more ideal platform for realizing flexible SoC: Xilinx makes it "All-Programmable System-on-Chip (APSoC, All-Programmable SoC)". It perfectly integrates the software programmability of the processor with the hardware programmability of the FPGA to provide unparalleled system performance, flexibility and scalability.
ZYNQ is composed of two main parts: a processing system (PS, Processing System) composed of dual-core ARM Cortex-A9 as the core, and a programmable logic (PL, Programmable Logic) part equivalent to a piece of FPGA. The simplified model of the ZYNQ architecture is shown in the figure below:
In the above figure, PS has a fixed architecture, including the processor and system memory; while PL is completely flexible, giving designers a "blank canvas" to create customized peripherals.
On ZYNQ, ARM Cortex-A9 is an application-level processor that can run an operating system like Linux, and the programmable logic is based on the Xilinx 7 series FPGA architecture.
The ZYNQ architecture implements the industry-standard AXI interface, and achieves a high-bandwidth, low-latency connection between the two parts of the chip. This means that both the processor and the logic part can be used to their best use, without incurring the interface overhead between two discrete devices. At the same time, the benefits of the system being simplified into a single chip can be obtained, including the reduction of physical size and overall cost.