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. …

Read the full article in the October 327 issue of Circuit Cellar

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PC/104 Card Features DMP Vortex DX-3 SoC

WIN Enterprises has announced the MB-83310, a PC/104 module featuring the economical DMP Vortex86 DX3-9126 processor which is mounted onboard. Power consumption of the dual-core SoC is only approximately 6W. The unit supports multiple VGA-LVDS displays with a maximum resolution of 1920×1440 at 60Hz. Operating systems support includes Microsoft Windows and Linux. The device is ideal for IIoT domain gateways, home IoT gateways, thin clients, and NAT Routers.

WIN Enterprises MB-83310 Editors

The board meets the PC/104 Specification 2.6 and supports the PC/104+ and PC/104 connector onboard. On board memory includes 2 Gbytes of DDR3L 1333. Its dual LAN connector with 2×10 pin header (1 x GbE,1 x Fast Ethernet). I/O consists of 4x USB 2.0, 2x COM Port (COM2 Port is RS-232/422/485, COM1 (RS232 only). For mass storage, there is 1x SATA Port (1×7 Pin),1xM.2 Socket (2242 only). The board’s DC 5V Power input is AT/ATX mode select by jumper. Operating temperature ranges from -20° C to 70° C.

WIN Enterprises | www.win-ent.com

Don’t Miss Circuit Cellar’s Analog & Power Newsletter

Analog & Power is where stuff gets real. Converting signals to and from analog is how embedded devices interact with the real world. And without power supplies and power conversion, electronic systems can’t do anything. Circuit Cellar’s Analog & Power MFG_IB048E096T40N1-00themed newsletter is coming to your inbox tomorrow.

This newsletter content zeros in on the latest developments in analog and power technologies including DC-DC converters, AD-DC converters, power supplies, op-amps, batteries and more.

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Microcontroller Watch. This newsletter keeps you up-to-date on latest microcontroller news. In this section, we examine the microcontrollers along with their associated tools and support products.

IoT Technology Focus. The Internet-of-Things (IoT) phenomenon is rich with opportunity. This newsletter tackles news and trends about the products and technologies needed to build IoT implementations and devices.

Embedded Boards. This content looks at embedded board-level computers. The focus here is on modules—Arduino, Raspberry Pi, COM Express, and other small-form-factor —that ease prototyping efforts and let you smoothly scale up production volumes.

PC/104-Plus SBC Features On-Board TPM Security

Versalogic is now shipping the “Liger”-a new high-performance PC/104-Plus single board computer (SBC). Based on Intel’s Kaby Lake processor, Liger combines high performance processing and high performance video with moderate power consumption (12 to 14 W typical). It features hardware-level security using an on-board Trusted Platform Module (TPM) security chip, and backwards compatibility with systems using PC/104-Plus (ISA or PCI) expansion.

PR_EPM-43_HI

Liger is designed for applications which require extreme CPU and video processing performance in a compact 108 x 96 mm (4.3 x 3.8″) PC/104 footprint.The Liger’s on-board TPM security chip can lock out unauthorized hardware and software access. It provides a secure “Root of Trust” processing environment for defense, medical, and industrial applications that require hardware-level security functions. Additional security is provided through built-in AES (Advanced Encryption Standard) instructions.

Versalogic | www.versalogic.com

Don’t Miss Circuit Cellar’s Newsletter: Embedded Boards

Board-level embedded computers are a critical building block around which system developers can build all manor of intelligent systems. Circuit Cellar’s Embedded Boards themed newsletter is coming to your inbox tomorrow. COM Express mm

The focus here is on module types like Arduino, Raspberry Pi, COM Express, and other small-form-factor modules that ease prototyping efforts and let you smoothly scale up to production volumes.

Already a Circuit Cellar Newsletter subscriber? Great!
You’ll get your “Embedded Boards” themed newsletter issue tomorrow.

Not a Circuit Cellar Newsletter subscriber?
Don’t be left out! Sign up now:

Remember, our new enhanced weekly CC Newsletter will switch its theme each week, so look for these in upcoming weeks:

Analog & Power. This newsletter content zeros in on the latest developments in analog and power technologies including DC-DC converters, AD-DC converters, power supplies, op-amps, batteries, and more.

Microcontroller Watch. This newsletter keeps you up-to-date on latest microcontroller news. In this section, we examine the microcontrollers along with their associated tools and support products.

IoT Technology Focus. The Internet-of-Things (IoT) phenomenon is rich with opportunity. This newsletter tackles news and trends about the products and technologies needed to build IoT implementations and devices.

Client Profile: SCIDYNE Corp.

About SCIDYNE
SCIDYNE has been designing and manufacturing electronic products for more than two decades. Headquartered in the United States, SCIDYNE serves both domestic and international OEM customers by being a trusted and reliable source of high-quality embedded system products. SCIDYNE’s line of PC/104 peripherals can be found in many diverse and demanding applications (e.g., industrial automation, medical equipment, and aerospace). Recent trends in the embedded market including the growing maker culture, powerful low-cost development platforms, and collaborative development has provided additional opportunities to offer new products designed especially for these segments.

Scidyne-xmem

Why Should Circuit Cellar Readers Be Interested?
The XMEM+ plugs onto an ordinary Arduino MEGA2560 and boosts available SRAM to over 512K. By increasing SRAM, the MEGA becomes much more capable in sophisticated applications. The SRAM is organized as 16 banks of 32K each. On-board high-speed logic simplifies bank-switching management. The active 32K bank seamlessly follows the internal 8K SRAM making 40K available at any time. Also included is a fixed 23K expansion bus for prototyping off-board parallel circuitry. Buffered control, data, and address signals are fully accessible. The operating logic level for all buffered signals is configurable as 3.3 or 5 V for proper translation when working with modern mixed voltage circuitry. The XMEM+ operates at the full 16-MHz system clock speed. Additional details are available at: www.scidyne.com/hpb7699.html.

Low-Power Micromodule

The ECM-DX2 is a highly integrated, low-power consumption micromodule. Its fanless operation and extended temperature are supported by the DMP Vortex86DX2 system-on-a-chip (SoC) CPU. The micromodule is targeted for industrial automation, transportation/vehicle construction, and aviation applications.
The ECM-DX2 withstands industrial operation environments for –40-to-75°C temperatures and supports 12-to-26-V voltage input. Multiple OSes, including Windows 2000/XP and Linux, can be used in a variety of embedded designs.

AvalueThe micromodule includes on-board DDR2 memory that supports up to 32-bit, 1-GB, and single-channel 24-bit low-voltage differential signaling (LVDS) as well as video graphics array (VGA) + LVDS or VGA + TTL multi-display configurations. The I/O deployment includes one SATA II interface, four COM ports, two USB 2.0 ports, 8-bit general-purpose input/output (GPIOs), two Ethernet ports, and one PS/2 connector for a keyboard and a mouse. The ECM-DX2 also provides a PC/104 expansion slot and one MiniPCIe card slot.

Contact Avalue Technology for pricing.

Avalue Technology, Inc.
www.avalue.com.tw