The rise of high-speed 8-bit network MCU

By the 1990's, corporations and businesses began to operate under the World Wide Web (WWW), and online users increased dramatically with email and e-commerce as significant driving forces.

The ensuing Internet era will augment the computer-to-computer networks of the 1980's and the user-to-user networks of the 1990's with Internet capable devices, resulting in the rise of M2M communication and the so-called "Ubiquitous Network Society."

The microcontroller used in embedded system design is primarily focused on control capabilities, where integration is the primary objective. Based on the target application, chip designers will incorporate different degrees of memory, input/output interface, and computational ability into a single controller.

Generally, microcontrollers integrate a variety of serial or parallel peripheral interfaces with GPIO (general purpose input/output) capabilities. Serial interfaces include UART, SPI , I2C, Microwire and 1-wire.

The parallel interface is linked to other chips using an external memory interface (EMI), local bus interface (LBI), or PCI bus interface. A microcontroller can be configured to be a Slave host, at which point any other controller configured as Master host can communicate to the Slave using a conventional 8/16-bit parallel interface. The timing functions can be achieved through a watchdog timer, timers/counters, programmable counter array (PCA), or a real-time clock(RTC).

The inclusion of other interfaces depends on specific applications. For example, speech channel applications build in I2S, AC'97, SP/DIF or other speech codecs. Consumer electronics build in USB, USB OTG, LCD controllers/drivers, and possibly include MMC or SD memory card interfaces.

Battery or module controllers build in SMBus, industrial automation applications build in CAN controllers, automobile data communications build in CAN/LIN controllers. LAN applications use network controllers with built-in 10/100Mbits Ethernet MAC/PHY. Figure 1 below depicts the 8-bit network network-capable microcontroller discussed in this article and it's I/O interface and applications.

Figure-1 Application diagram of High-speed 8-bit network MCU

Based on its ease of use, low cost, high bandwidth, stability, security, and compatibility across devices, Ethernet has become the de facto standard of network access.

Today, Ethernet has surpassed the use of both SOHO and enterprise networks and expanded into consumer electronics, gradually becoming the most attractive solution for embedded systems to access the network.

With the growth of home networking, media sharing, and the gradual prevalence of hi-definition content, the expansion of high bandwidth Ethernet connections to other non-PC devices in the home is also on the rise. In addition, the stability and security of Ethernet makes it an attractive solution for more industrial applications as well.

The proliferation of M2M communications anticipates a rise in Ethernet-capable microcontroller market. Ethernet can be applied to include a broad range of products, from household appliances, factory and industrial automation, security systems, remote surveillance and management, environmental observation, remote data accumulation, and other applications.

In recent years, the market for microcontrollers has shifted away from consumer electronics to data/telecommunications, resulting in increased demand of high-powered 32-bit microcontrollers for advanced products.

However, as the prices of 8-bit microcontrollers have plateaued and begun to decrease, they have been singled out as the low cost solution for M2M and networking devices. How does one increase the performance of the 8-bit controller? How does one increase the network bandwidth? The question of how to achieve a high level of integration yet maintaining the cost-cutting and miniaturization demands of the market are the key issues facing today's chip designers.