Emulating Legacy Interfaces

Do It with Microcontrollers

There’s a number of important legacy interface technologies—like ISA and PCI—that are no longer supported by the mainstream computing industry. In his article Wolfgang examines ways to use inexpensive microcontrollers to emulate the bus signals of legacy interconnect schemes.

By Wolfgang Matthes

Many of today’s PC users have never heard of interfaces like the ISA bus or the PCI bus. But in the realm of industrial and embedded computers, they are still very much alive. Large numbers of add-on cards and peripherals are out there. Many of them are even still being manufactured today—especially PCI cards and PC/104 modules for industrial control and measurement applications. In many cases, bandwidth requirements for those applications are low. As a result, it is possible to emulate the interfaces with inexpensive microcontrollers. That essentially means using a microcontroller instead of an industrial or embedded PC host.

Photo 1 - The PC/104 specifications relate to small modules, which can be stacked one above the other.

Photo 1 – The PC/104 specifications relate to small modules, which can be stacked one above the other.

To develop and bring up such a device is a good exercise in engineering education. But it has its practical uses too. Industrial-grade modules and cards are designed and manufactured for reliability and longevity. That makes them far superior to the kits, boards, shields and so on, that are intended primarily for educational purposes and tinkering. Moreover, a microcontroller platform can be programmed independently—without operating systems and device drivers. These industrial-grade boards can operate in environments that consume considerably less power and are free from the noise typical of the interior of personal computers. The projects depicted here are open source developments. Descriptions, schematics, PCB files and program sources are available for downloading.

Fields of Use

The basic idea is to make good use of peripheral modules and add-in cards. Photo 1 shows examples. Typical applications are based on industrial or embedded personal computers. The center of the system is the host—the PC. Peripheral modules or cards are attached to a standardized expansion interface, that is, in principle, an extended processor bus. That means the processor of the PC can directly address the registers within the devices. The programming interface is the processor’s instruction set. As a result, latencies are low and the peripheral modules can be programmed somewhat like microcontroller ports—without regard to complicated communication protocols. For example, if the peripheral was attached to communication interfaces like USB or Ethernet, that would complicate matters. Common expansion interfaces are the legacy ISA bus, the PCI bus and the PCI Express (PCIe) interface. …

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COM Express Type 10 Mini Board Boasts Wide Temp Range

Axiomtek has announced its latest COM Express Type 10 Mini Module, the CEM311. The CEM311 is scalable and features Intel Celeron processor N3350 or Intel Pentium processor N4200. Integrated with Intel Gen 9 graphics, and with the support of DX12.0, OCL 2.0 and OGL 4.3, the CEM311 delivers advanced graphics capability, 4K resolutions and high media performance. The rugged system on module supports a wide operating temperature range from -20°C to +70°C to ensure stable operation in harsh environments. Axiomtek image002The CEM311 is well suited for graphics-intensive, industrial IoT applications such as industrial control, medical imaging, digital signage, gaming, military, and networking.

This versatile board supports Windows 10 and Linux operating systems, and offers AXView 2.0 – Axiomtek’s proprietary intelligent remote management software that will make operating the solution/application easier.

Key Features:

  • COM Express Type 10 mini computer-on-module
  • Intel Pentium N4200 and Celeron N3350 processors (codename: Apollo Lake SoC)
  • Onboard 4 GB DDR3L-1600 memory, up to 8 GB
  • Optional eMMC 5.0, up to 64 GB
  • One LPC bus is available for easy connection of legacy I/O interfaces.
  • Up to 4 lanes of PCI Express
  • Two SATA-600 ports
  • Wide voltage range of 4.75 V – 20 V DC-in power input
  • 1 GbE, 2 USB 3.0 and 8 USB 2.0
  • Intelligent remote management software AXView 2.0

Axiomtek | www. axiomtek.com

Software Targets Data Acq for Desktop Python under Linux

Microstar Laboratories has released DAPtools for Python software, an API that enables high-performance data acquisition applications using the Python programming language on desktop GNU/Linux systems. This is not a reduced or specialized language variant—it supports the complete, full-featured Python environment and complements the Accel64 for Linux software that provides access to DAP board features and functions. Typical applications are one-time diagnostic tests, academic research, and automatically-configurable scripting for test automation.


The DAPIO programming interface behind DAPtools for Python provides the same stable DAPL system services that all other high-level programming environments have used over the last 20 years. Access to that interface is through a Linux dynamic library, which Python applications can load and access using the ctypes library. DAPtools for Python presents the low-level interface as a simple “interface object” and some utility functions to make the DAP board interactions work like familiar Python objects and functions. The programming is a lot like connecting to a networked resource: open a connection, specify the data acquisition actions required, run the configuration, take the requested data, and close the connection when finished.

Microstar Laboratories | www.mstarlabs.com

Fanless Small Form Factor PC System

HABEYThe BIS-3922 improves on HABEY’s BIS-6922 system by offering additional I/O for more applications and solutions. The system is well suited for automation, digital signage, network security, point of sale, transportation, and digital surveillance applications.
The BIS-3922 system includes six DB9 COM ports on the front panel, one of which supports RS-232/-422/-485. HABEY’s proprietary ICEFIN design ensures maximum heat dissipation and a true fanless system.

The BIS-3922 system is built with the Intel QM77 chipset and is compatible with the third-generation Ivy Bridge Core processors. The BIS-3922 system’s additional features include a HM77 chipset that supports third-generation Intel Core i3/i5/i7 processors; dual gigabit Ethernet ports; High-Definition Multimedia Interface (HDMI), video graphics array (VGA), and low-voltage differential signaling (LVDS) display interfaces; one mini-PCI Express (PCIe) and one mSATA expansion; and a 3.5” single-board computer (SBC) form factor.

Contact HABEY for pricing.


Real-Time Processing for PCIe Digitizers

Agilent U5303A PCIe 12bit High-Speed DigitizerThe U5303A digitizer and the U5340A FPGA development kit are recent enhancements to Agilent Technologies’s PCI Express (PCIe) high-speed digitizers. The U5303A and the U5340A FPGA add next-generation real-time peak detection functionalities to the PCIe devices.

The U5303A is a 12-bit PCIe digitizer with programmable on-board processing. It offers high performance in a small footprint, making it an ideal platform for many commercial, industrial, and aerospace and defense embedded systems. A data processing unit (DPU) based on the Xilinx Virtex-6 FPGA is at the heart of the U5303A. The DPU controls the module functionality, data flow, and real-time signal processing. This feature enables data reduction and storage to be carried out at the digitizer level, minimizing transfer volumes and accelerating analysis.

The U5340A FPGA development kit is designed to help companies and researchers protect their IP signal-processing algorithms. The FPGA kit enables integration of an advanced real-time signal processing algorithm within Agilent Technologies’s high-speed digitizers. The U5340A features high-speed medical imaging, analytical time-of-flight, lidar ranging, non-destructive testing, and a direct interface to digitizer hardware elements (e.g., the ADC, clock manager, and memory blocks). The FPGA kit includes a library of building blocks, from basic gates to dual-port RAM; a set of IP cores; and ready-to-use scripts that handle all aspects of the build flow.

Contact Agilent Technologies for pricing.

Agilent Technologies, Inc.