Traditional hardware-first, software-later embedded system design requires repeated modifications and trials. The entire design process relies heavily on the designer's experience, resulting in high design cycles and development costs. During these repeated modifications, deviations from the original design requirements are often observed. Hardware-software co-design is a novel system design approach proposed to address these issues. Based on system objectives, it comprehensively analyzes the system's hardware and software functions and existing resources to maximize the concurrency between hardware and software, co-designing the hardware and software architecture to ensure the system operates at its optimal state. This design method fully utilizes existing hardware and software resources, shortens the system development cycle, reduces development costs, improves system performance, and avoids the drawbacks of independently designing the hardware and software architecture. Applying this design approach to actual product development relies heavily on EDA tools. This article will briefly introduce several mature collaborative design EDA tools . 1. Comparison of Collaborative Design and Traditional Design Methods Embedded systems consist of several functional modules, which can be categorized into software modules and hardware modules according to their nature. Over the past few decades, system design methodologies have undergone significant changes, ranging from top-down to modular design. Both are generally hardware-module-first approaches, collectively referred to as traditional design methods. This approach separates hardware and software into two independent parts. Throughout the design process, a "hardware-first principle" is typically adopted, meaning that hardware design is performed first, based on a rough estimate of software requirements, followed by software design on that hardware platform. Due to a lack of clear understanding of the software architecture and implementation mechanisms during hardware design, the work is somewhat arbitrary. System optimization, limited by design space, can only improve the performance of individual hardware/software components, making comprehensive system optimization impossible. The resulting design often fails to fully utilize hardware and software resources, making it ill-suited for modern, complex, large-scale system design tasks. Embedded system hardware-software co-design, on the other hand, allows software and hardware design to be designed concurrently as a whole, finding the optimal integration point for efficient system operation. A key advantage of hardware-software co-design is the interaction between hardware and software design throughout the design process, occurring at various stages and levels. The design process fully embodies the synergy between software and hardware. Existing software and hardware resources are considered during the allocation of software and hardware functions. Software and hardware support each other during the design and simulation evaluation of software and hardware functions. This allows software and hardware functional modules to integrate early in the design and development process, enabling early problem detection and resolution, avoiding (or at least reducing) repeated system modifications and related issues in the later stages of design and development. It also facilitates unlocking system potential, reducing product size, lowering system costs, and improving overall system performance. 2. The Process of Software-Hardware Co-design In general, the system design process of software-hardware co-design can be divided into four stages: system description, system design, simulation verification, and synthesis implementation. System description is the process of comprehensively describing the functions and performance of the embedded system to be designed using one or more system-level description languages, establishing the system's software and hardware models. System modeling can be done manually by the designer using informal language or even natural language, or it can be achieved with the help of EDA tools. Manual modeling can easily lead to inaccurate system descriptions, requiring modifications to the system model in subsequent processes, thus complicating the system design. Excellent EDA tools can overcome these drawbacks. For embedded systems, system design can be divided into two stages: hardware/software function allocation and system mapping. Hardware/software function allocation determines which system functions are implemented by hardware modules and which by software modules. Hardware generally offers better performance, while software is easier to develop and modify, and has a relatively lower cost. Due to the configurability and programmability of hardware modules, as well as the hardware-based and firmware-based implementation of certain software functions, some functions can be implemented using both software and hardware, blurring the lines between hardware and software. Furthermore, hardware/software function allocation must consider not only the availability of market resources but also system cost, development time, and many other factors. Therefore, hardware/software function allocation is a complex and arduous process, and it is the most crucial step in the entire task flow. System mapping involves selecting the system's hardware and software modules and their interface implementations based on the system description and hardware/software task partitioning, integrating them, and ultimately determining the system architecture. Specifically, this process determines which hardware modules (e.g., fully custom chips, MCUs, DSPs, FPGAs, memory, I/O interface components), software modules (embedded operating systems, drivers, functional modules), and communication methods between these modules (e.g., buses, shared memory, data channels) and their specific implementation methods will be used. Simulation verification is the process of verifying the correctness of the system design. It evaluates the correctness of the design results to avoid repeated modifications when problems are discovered during system implementation. During system simulation verification, the simulated working environment differs significantly from actual use, and the interaction methods and effects between hardware and software also differ, making it difficult to guarantee the system's reliability in a real environment. Therefore, the effectiveness of system simulation is limited. Hardware/software synthesis is the concrete fabrication of the software and hardware system. After simulation verification, the system can be fabricated according to the system design requirements, i.e., designing the hardware and software according to the aforementioned requirements and ensuring they work in harmony. Once fabricated, field experiments can be conducted.