AZ QBUS v1.02

AZ QBUS is a modern AZ-series controller designed for PDP-11 minicomputers and compatible systems using the QBUS bus. It belongs to the AZ controller family created specifically for PDP-11 platforms and is intended for convenient disk-image storage and access using MicroSD media. Official AZ project website.

The AZ controller family was developed by engineers Max Bagaev and Alexander Zabayratsky in 2019. According to the official AZ website, more than 500 controllers of different modifications have been produced since then, making AZ the most widely produced modern hardware platform for PDP-11 systems. In the official documentation, AZ QBUS v1.02 is listed as the dedicated QBUS version and is described as functionally corresponding to MPI version 1.01. :contentReference[oaicite:3]{index=3}

The core idea behind AZ QBUS is to provide a random-access block device where a disk image exists as a regular file inside the controller’s own storage filesystem. This makes disk-image handling much easier than with legacy storage devices. The platform also extends beyond basic storage by offering Ethernet connectivity, a built-in WebDAV server, the ability to open RT-11 disk images as directories, a real-time clock, and NTP-based time synchronization. Learn more at az.maxiol.com.

Key Features

• Designed for PDP-11/QBUS: a dedicated controller version for QBUS-based systems and compatible machines
• MicroSD-based storage: disk images are stored as regular files on a memory card
• Up to 32 emulated devices: a single controller can emulate up to 32 devices on one MicroSD card
• Card support: compatible with MicroSD and MicroSDHC; SDXC cards are not supported
• Networking: supports 10 Mbit wired Ethernet, built-in WebDAV, and network drives via MAXIOL Landisk
• RT-11 image access: allows remote read, write, delete, and rename operations inside RT-11 disk images
• RTC and NTP: includes a real-time clock and supports time synchronization from NTP servers
• Open API: suitable for custom software and driver development; open-source RT-11 drivers are available
• Non-volatile memory: includes a dedicated memory block accessible through the API

Compatibility and Architecture

• Supported operating systems: RT11*, RSX11M, and various systems created for BK-series computers
• Bus support: supports 16-bit, 18-bit, and 22-bit address buses
• Controller addresses: occupies MPI addresses 177220-177226; 177220 is CSR, 177222 is the Data Register, and 177224/177226 are PROM bootloader registers
• Boot startup: the bootloader can be started with 177226G or 177224G
• Hardware platform: classic AZ controllers are based on a single STM32F407VET6 microcontroller without additional RAM

Why It Matters

AZ QBUS makes modern use of vintage PDP-11 systems much more practical. Instead of relying on rare and difficult-to-maintain legacy storage devices, users get a compact controller with MicroSD image storage, network access, and flexible remote file management. This makes it especially attractive for enthusiasts, restorers, museums, and engineers working with real PDP-11 hardware. :contentReference[oaicite:4]{index=4}

Useful links:
Official AZ MAXIOL website
Russian version
AZWIKI documentation