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Home > Technologies > ConnectMe ConnectMe and WiMe: This
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copyright Digi Inc.Digi Inc. offers a product family called the ConnectMe/WiMe. These are highly capable 32 bit ARM processors with moderate amounts of RAM and Flash. They support embedded Linux in addition to a variant of the ThreadX RTOS with NetSilicon extensions, called NetOS. The device is programmed in C using a Gnu cross complier. The wired device draws only 300 mA; both devices run on 3.3 VDC. Their back end is a logic-level serial line with configurable baudrate and several lines configurable as serial handshake or GPIO lines. The wired module supports power over ethernet. Both units can be ordered with standard Ethernet-to-serial software, or as fully customizable units. The ConnectMe/WiMe has extremely low unit cost, making it attractive for many cost sensitive applications that would normally not support an Ethernet interface. However, the moderate compute capacity and limited back end I/O limit those applications functionally. While the boot loader has improved and the the cost of development tools has been reduced, mainly in 2008, the documentation is still difficult and there is a learning curve that presents a moderate barrier to entry. In addition, well intentioned toolchain improvements often "break" features and workarounds in legacy code, making the ConnectMe an interesting device to work with. More details on the latter points are at: https://DigiConnectMeNotes.blogspot.com GlueLogix recommends the ConnectMe/WiMe for moderate to high volume applications where the development cost can be spread over many units, and the I/O and computation requirements are appropriate to embedded ARM and RTOS capabilities. GlueLogix has created a number of high level network applications with realtime serial backends that run on the Digi ConnectMe. The ConnectMe (wired) and WiMe (WiFi) are better than standard network-serial adapters because they are smart. They can be programmed to emulate many common network devices, with a backend that matches your application. Our largest ConnectMe application so far (fall 2008) included an embedded web server with custom Server Side Includes and macro language based on Forth. A typical custom ConnectMe/WiMe application looks like this:  GlueLogix Open Source Project (2004):Remote RS232 PortThis started out being a much more complex design, with interesting software, but then the recession hit. Electronics companies were forced to come out with new products, and at least two had the idea of encapsulating a network server in an RJ45 shell. Of the two, Digi's solution is by far the more capable design, with 2 MB of memory, an ARM processor, and a high speed serial port with digital I/O (configurable as handshake or GPIO).The Digi product is called the ConnectMe. It provides Ethernet connectivity to any design with 300 mA available at 3.3 volts. The companion product, WiMe, shares the same footprint and all interfaces, but gives you 802.11 connectivity. Here's the URL: https://www.digi.com/products/embeddeddeviceservers/digiconnectme.jsp The software that comes with the ConnectMe is more than adequate for a remote serial port or I/O monitor. Among its many functions are the ability to wait for serial traffic, open a TCP session with a configured host, and forward that traffic to the configured host, closing the connection afterwards. You can write your own software too. Digi sells two levels of development kit, one for people who want to use and extend the default software, and another for people who want to take over the system with a new application all their own. The design presented here is a minimal life support system for the ConnectMe with RS232 level translation and a simple power supply. The schematic is drawn in gEDA. 17Nov04: Since first posting this project, I have written software that loads onto the Connectme, replacing Digi's standard firmware. As it turned out, it was quite an adventure. Read all about it on my ConnectMe blog: https://DigiConnectMeNotes.blogspot.com |
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