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Device Profile: Connect Tech Blue Heat/Net Ethernet-to-serial adapters

Jun 16, 2005 — by LinuxDevices Staff — from the LinuxDevices Archive — 23 views

Connect Tech used uClinux as the embedded software platform within a line of compact, intelligent Ethernet-to-serial interface adapters introduced last year. The Blue Heat/Net devices enable remote monitoring of a wide range of serial-interfaced equipment over the Web or on a local network, without requiring a dedicated PC.

The Blue/Heat Net contains an embedded uClinux OS
(Click to enlarge)

Basically, the Blue Heat/Net devices communicate using “legacy” RS-232, RS-422, or RS-485 serial ports with equipment that lack modern network interfaces, and pass commands and data back and forth to/from remote hosts over an Ethernet interface. Additionally, the devices can be programmed to provide customized services such as protocol conversion, data translation, or other application-specific tasks.

The devices are suitable for applications in industrial monitoring and control, retail POS (point-of-sales/service), building automation, transportation systems, patient monitoring, according to Connect Tech.

Blue Heat/Net used in industrial automation

The Blue Heat/Net devices are available in several models, having up to eight serial ports. Serial data rates range from 50 bps to 460.8 Kbps, depending on the type of serial interface. The devices also include an auto-sensing 10/100Mbps Ethernet LAN port and several diagnostic LEDs. Some models provide DIN rail mounting and Power-over-Ethernet (PoE) features.

The devices can be configured by means of a Web-based interface, via Telnet, or locally by means of a direct serial connection.

Configuring Blue/Heat Net over the Web
(Click to enlarge)

Supported remote communications protocols include TCP/IP, UDP, ARP, TFTP, DHCP, BOOTP, HTTP, and PPP, among others. In addition, Connect Tech provides a “virtual COM port” network protocol layer which allows a remote application to transparently communicate with serially-interfaced equipment through the Blue Heat/Net device, without needing to be aware that it is doing so over the Internet.

The devices can boot from internal Flash memory, or over a network, and they provide the means to update their embedded software remotely.

Under the hood

The Blue Heat/Net's embedded computer consists of a ColdFire SoC (system-on-chip processor), along with 16MB SDRAM, 2MB Flash, and quad UARTs. The device's embedded Linux software is derived from uClinux 20020927, based on a 2.4.19 kernel.

Other open-source software components used in the device's embedded software stack include the JFFS2 flash filesystem, the ubiquitous BusyBox, and the BOA embedded webserver, along with telnetd, gettyd, Inetd, PPPD, DNSMASQ, DHCPCD.

The company says it did the product's uClinux software development internally, without making use of outside commercial embedded Linux vendors.

Connect Tech offers a free uClinux-based SDK (software development kit), to enable developers to create customized protocols and download them directly into Flash memory inside the Blue Heat/Net devices. The company points out that the Blue/Heat Net's embedded uClinux operating system offers a “familiar Linux API” (application programming interface), and that the SDK includes “a full range of open source development tools.”


Connect Tech's Blue Heat/Net Ethernet-to-serial adapters are available now, in 2, 4, and 8 port models. They range in price from $130 to $660 USD, depending on configuration. More details on the Blue Heat/Net devices are available on Connect Tech's website.

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