Board enters crowded arena at $999 price point

By Patrick Mannion, contributing editor

With the launch of the HiFive
Unleashed, SiFive puts the RISC-V architecture in the hands of developers and
provides a unique alternative in an arena crowded with sameness.

It’s not that sameness isn’t
good: For long-term stability and support, there’s nothing quite like the
reassurance of a continuous stream of powerful Intel x86 single-board computers
(SBCs) in various form factors for embedded applications. Likewise, for
Arm-based SBCs, from the hobbyist and maker SBCs like Raspberry Pi to rugged and
embedded, Arm provides the core support and roadmap while the community
provides the ICs, board, OS, and application software.

There was a time when x86 was
differentiated from Arm by having Windows support, but then Microsoft developed
Windows 10 versions for both Arm-based IoT devices and, more recently, for
laptops. Now Arm can add Windows to an OS list that includes Android and Linux.
Meanwhile, the x86 already has strong Linux support.

This wide base of support was
why eyebrows were raised when the new, license-free RISC-V architecture was
announced: Why would anyone design around an architecture with no real support,
ecosystem, or tools? Still, RISC-V gathered steam, getting a big boost when
Nvidia decided in 2016 that it would use RISC-V as the foundation for a
replacement of its proprietary Falcon controller.

While the RISC-V ISA was
originally intended as a low-power, highly efficient, open-source architecture,
that did not preclude powerful implementations. The first such implementation
is SiFive’s Freedom U540 quad-core, 1.5-GHz system-on-chip (SoC), the first
RISC-V implementation to support Linux. That SoC is the heart of SiFive’s
just-released HiFive Unleashed, Linux-supported SBC for developers (Fig. 1).


Fig. 1: The HiFive Unleashed SBC supports Linux and is based on SiFive’s
quad-core, 1.6-GHz, SoC implementation of the RISC-V open-source ISA.

Around the Freedom U540,
SiFive has placed 8 Gbytes of DDR4 with ECC (the U540 supports up to 64 Gbytes),
32 Mbytes of quad SPI flash from ISSI, a microSD slot for extra storage, and an
FMC-connector expansion slot. The board costs $999 and is available now.

All Arm, no leg
While the opportunity to
develop around the RISC-V with Linux may in itself be sufficient reason to
spend $999, designers of industrial embedded applications don’t have to spend
an arm and a leg to get the performance that they need. Take the TS-7970 SBC
from Technologic Systems (Fig. 2).


Fig. 2: The rugged, industrial-oriented Technologic Systems TS-7970 SBC
costs $229 and is based on an Arm Cortex-A9 with one or four cores.

Based on the NXP i.MX6 Arm
Cortex-A9 single- or quad-core CPU running at 800 MHz or 1 GHz, respectively, the
board is tuned for high-performance, environmentally challenging applications.
As such, it comes with screw-down power and I/O terminals and has an operating
temperature range of –40°C to 85°C (in a fanless enclosure).

The roster of I/O support
includes wireless (Wi-Fi and Bluetooth), dual gigabit Ethernet ports,
multimedia support (HDMI, LVDS, and audio), and SATA II, MiniCard, digital I/O,
analog-to-digital converter, Modbus, USB, and CAN. It consumes under 3 W
(typical) and approximately 15 mW in sleep mode.

On the OS side, it supports
Linux (Kernel, Debian, Yocto, Ubuntu, and Ubuntu Core), Android, and QNX
Neutrino RTOS.

Intel NUC gets industrial-strength facelift
Late in 2017, Intel launched
the NUC7i5DNBE, a version of its Next Unit of Computing (NUC)-form-factor SBCs,
this one with its 7th-Generation iCore processors (i5-7300U). While
the NUC is widely known as a standalone PC or workstation, the NUC SBC has some
tweaks to make it more suited to more rugged, embedded applications (Fig. 3).


Fig. 3: The NUC7i5DNBE SBC from Intel uses its 7th-gen iCore
processors with ruggedization features such as a soldered-down BGA and
solid-state memory.

The board keeps the same 4 x 4-in.
form factor but has a soldered-down BGA for the processor and SSD memory
instead of a rotating-platter hard drive. It dissipates 15 W and runs off a 12-
to 24-Vdc supply. The board comes with up to 32 Gbytes of DDR4-2133 1.2-V
SO-DIMM memory, integrated graphics, and can drive up to three displays. It
supports Windows and Linux.

Costing $384, it’s hard to
overlook the combination of performance and I/O. The i5 Core is clocked at up
to 3.5 GHz and has up to 3 Mbytes of cache. The I/O includes PCI Express Gen 3,
dual HDMI 2.0a ports, four USB ports, two SATA ports, and one GbE port.

While the board comes with a
fan, for industrial applications, this can be removed and the board placed in a
fanless enclosure. Logic Supply has already done this for the NUC with its
ML100G-31 enclosure. This includes a custom-designed heatsink to maximize heat
transfer from the processor to ambient (Fig. 4).


Fig. 4: The ML100G-31 ruggedized enclosure for the NUC comes with a
custom heatsink to maximize heat transfer from the processor to ambient.

Removing the fan greatly
increases reliability as it eliminates the fan as a failure mechanism and
limits moisture, dust, and metal ingress. However, Logic Supply will also mask
off unused ports to further isolate the inside from the environment. The base
chassis costs $695.

It’s hard to mention form
factors without including one of the most compact and rugged of all: COM Express
Mini, measuring in at 2.2 x 3.3 in. (Fig. 5).


Fig. 5: The NanoCOM-KBU is the first COM Express Type 10 mini board to
support Intel’s 7th-gen Core processors.

Within these confines, AAEON developed the
NanoCOM-KBU, the first COM Express Type 10 board with a 7th-Gen Core
processor and Intel graphics support. It comes with 4 Gbytes of memory. AAEON
has also upgraded the embedded controller structure with a real-time interrupt
for faster response. It also comes with an I2C port to connect with external ICs, and
port-wise, it includes 1 GbE port, eight USB 2.0 and two USB 3.0 ports, two
SATA II interfaces, and four PCIe expansion slots. Pricing is as yet