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S-100 虚拟工作台是一个基于网页的模拟器，用于重现 20 世纪 70 、 80 年代的 S-100 总线计算机系统。用户可以通过拖放卡片库向虚拟 S-100 机箱装配硬件，配置并运行诸如 Altair 8800 、 IMSAI 8080 和 Processor Technology SOL-20 等经典系统。平台提供多种预设配置（例如运行 CP/M 2.2 并配置 64K RAM 的 Altair 8800），也可在可用插槽中添加 CPU 、内存、 I/O 和存储卡来自行组建自定义系统。

模拟器支持包括 Intel 8080 和 Zilog Z80 在内的多种 CPU，提供精确的指令集仿真和可调的时钟速率。内存选项包括可配置地址范围的静态 RAM 卡和可加载内置或自定义二进制映像的 ROM 卡，并通过虚拟 I/O 端口支持影子 ROM 行为。串行 I/O 由可配置的 UART 卡处理（如 MITS 88-2SIO 和通用 SIO 设备），为运行 CP/M 等操作系统提供控制台输入输出。

存储仿真涵盖硬扇区和软扇区软盘控制器。 MITS 88-DCDD 控制器支持早期 Altair 使用的 IBM 3740 原始格式，而基于 WD1793 的 FDC 则兼容 IMSAI 、 Cromemco 及其他采用标准平面磁盘映像的非 MITS 平台。驱动器 A 到 D 可分别挂载磁盘映像文件，用户可从真实的 CP/M 磁盘映像启动并运行遗留软件。

图形与显示选项包括 Cromemco Dazzler 卡（从系统 RAM 中软件定义的帧缓冲生成复合视频输出，支持多种彩色与单色分辨率）和 Processor Technology VDM-1（提供内存映射文本显示，16 行 ×64 列 ASCII 字符、硬件滚屏和反显支持）。这些扩展使依赖图形或增强文本输出的软件能够进行直观交互。

界面还包含用于输入输出的终端模拟器、显示实时地址、数据信号与控制信号活动的总线分析仪，以及用于调试的总线跟踪日志。用户可以将 Intel HEX 文件直接加载到内存，使用运行、单步、重置和重启等命令控制执行并检查内存内容。系统精确仿真底层总线行为，包括 MEMR 、 MEMW 、 IOR 、 IOW 和 HOLD/HLDA 仲裁，为历史软件保存与教学提供了忠实的 S-100 总线环境再现。 This is a description of the S-100 Virtual Workbench, a web-based emulator for vintage S-100 bus computer systems from the 1970s and 1980s. The platform allows users to configure and run classic hardware setups, including the Altair 8800, IMSAI 8080, and Processor Technology SOL-20, using a drag-and-drop card library to populate a virtual S-100 chassis. Users can select from a range of preset configurations, such as an Altair 8800 running CP/M 2.2 with 64K RAM, or build custom systems by adding CPU, memory, I/O, and storage cards to available slots.

The emulator supports multiple CPU types, including the Intel 8080 and Zilog Z80, with accurate instruction set emulation and configurable clock rates. Memory options include static RAM cards with configurable address ranges and ROM cards that can load built-in or custom binary images, with support for shadow ROM behavior via phantom I/O ports. Serial I/O is handled through configurable UART cards like the MITS 88-2SIO and generic SIO devices, enabling console input and output for running operating systems like CP/M.

Storage emulation includes both hard-sector and soft-sector floppy disk controllers. The MITS 88-DCDD controller supports the original IBM 3740 format used by early Altair systems, while the WD1793-based FDC provides compatibility with IMSAI, Cromemco, and other non-MITS platforms using standard flat disk images. Disk drives A through D can be assigned disk image files, allowing users to boot and run legacy software from authentic CP/M disk images.

Graphics and display options include the Cromemco Dazzler card, which generates composite video output from a software-defined frame buffer in system RAM, supporting multiple color and monochrome resolutions. The Processor Technology VDM-1 provides memory-mapped text display with 16 rows by 64 columns of ASCII characters, hardware scrolling, and inverse video support. These cards enable visual interaction with software that relies on graphical or enhanced text output.

The interface includes a terminal emulator for user input and output, a bus analyzer showing real-time address, data, and control signal activity, and a bus trace log for debugging. Users can load Intel HEX files directly into memory, control execution with run, step, reset, and reboot commands, and inspect memory contents. The system accurately emulates low-level bus behavior, including MEMR, MEMW, IOR, IOW, and HOLD/HLDA arbitration, providing a faithful recreation of the S-100 bus environment for historical software preservation and education.