Kit has web and wireless designs on PIC micros

An innovative microcontroller development kit from Iosoft opens up new application vistas for developers of deeply embedded 8/16bit systems.

An innovative microcontroller development kit from Iosoft opens up new application vistas for developers of deeply embedded 8/16bit systems.

Providing the first reference design for interfacing PICmicro microcontrollers to 802.11b - including a lean web server - the kit provides a very low cost solution for Internet- and wireless-enabling real-time systems.

Developers of products such as home appliances and vending machines can now incorporate 'anywhere, anytime' duplex connectivity for monitoring, troubleshooting and upgrades - using the dominant wireless networking standard.

Priced at just US $257, GBP 165 or Eur 262, the ER21 development kit also features the option of a very low-cost software license.

Together, these reduce the NRE (nonrecurring engineering) intellectual property costs involved in web- and wireless-enabling to just cents per product.

"The standard nature of 802.11b Wi-Fi offers electronic OEMs a remarkably flexible and cost-effective option for adding universal connectivity to products", says Jeremy Bentham, Chief Technical Officer of Iosoft.

"This development kit gives designers the means to achieve that goal - with a suite of tools that can implement functionality ranging from remote alarms and monitoring, to design fixes and upgrades".

The ER21 development kit is a combination of a PCB with a PIC18xxx family microcontroller with Flash memory, in-circuit debug connector, and Ethernet and serial interfaces, linked to a commercial PCMCIA card for the 802.11b wireless network.

This approach ensures designers have a certified and approved radio, in a standardised form that may be purchased at competitive prices from numerous vendors (around US $60 in single quantities).

The other components required to implement the interface in embedded systems may be purchased at very low cost.

The kit comes with a circuit diagram, and comprehensive software support in the form of Chipweb Wireless - a new variant of Iosoft's pioneering lean TCP/IP protocol suite for microcontrollers.

Developed over three years, and shipped to more than 10,000 developers, the software provides a comprehensive range of connectivity protocols including TCP, IP, UDP, DHCP, HTTP, SMTP and POP3.

These protocols allow users to implement connectivity with features such as a web server, email capability and high-speed data transfer, in forms optimised for the small memory arrays available on microcontroller products.

Typical stack sizes are around 8Kword.

This is 50% of the program memory space on a PIC18xxx microcontroller (MCU) - assuring developers of the ability to perform both control and networking requirements with ease.

Full source code and a license for unlimited use in embedded systems are available for a modest one-time payment of US $1091, GBP 700 or Eur 1110.

For versatility of application, ER21 allows PICmicro-based embedded systems to communicate in 'ad-hoc' (IBSS) or 'infrastructure' (ESS) Wi-Fi modes.

IBSS or independent basic service set provides peer-to-peer connectivity, and is suitable for very small networks.

ESS or extended service set networks are more common and use radio hubs - known as access points - to co-ordinate traffic, maximising reliability and minimising power consumption.

Access points can also act as gateways into conventional Ethernet networks, allowing transparent communication between wired and wireless nodes - allowing any existing network software to be used on a wireless LAN with zero changes.

A key feature of the protocol suite is the provision of a lean HTTP web server.

It supports multiple connections, forms for simple remote configuration, and dynamically updated HTML web pages.

As supplied, the web server automatically provides an example web page showing Wi-Fi network and channel ID with the dynamic status of the wireless link using the signal strength indication provided by the PCMCIA card.

Another useful feature for embedded system developers is support for DHCP (Dynamic Host Configuration Protocol).

This provides a convenient means of managing and administering systems in the field, allowing systems to automatically obtain a temporary address on boot-up.

The software additionally supports the use of the wired equivalent privacy (WEP), with the extended encryption key of up to 128bit, providing security for embedded systems against attempts at unauthorised access.

The potential bandwidth of Wi-Fi is up to 11Mbit/s, with slower rates down to 1Mbit/s employed as an automatic fallback in the event of interference.

The transmission range of the standard is up to around 100m.

This is more than adequate for many typical target microcontroller applications, which spans home appliances such as heating controllers, air conditioning units and security systems, to commercial and industrial equipment such as vending machines in hotels and transport stations, and operator panels for machinery.

The ER21 module, with its serial and wireless Ethernet interfaces, can also serve in applications directly, as an addon module to perform a task such as protocol conversion.

The ER21 development kit costs US $257, GBP 165 or Eur 262 and is available for immediate shipment.

Full source code for the software is available for US $70, GBP 45 or Eur 71, and may be embedded in an unlimited quantity of systems for a one-time license fee of US $1091, GBP 700 or Eur 1110.

Including the development system, the total NRE expense for the development tool and intellectual property to implement the system in any number of products is just US $1418, GBP 910 or Eur 1443, which is equivalent to just one or two cents per product for medium volume consumer applications (50-100k units).

(Updated by CR, May 2007).

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