MediaTek LinkIt™ Smart 7688 and MediaTek LinkIt Smart 7688 Duo – which one is right for my project?

linkit smart 7688

When it comes to MediaTek LinkIt Smart 7688 development platforms, the first questions you might ask are “Which platform best fits my development purposes?” and “How do I choose the right version?” In this article we’ll provide some insights to help you decide which platform is best suited to your project.

Before diving into the differences between the two boards, let’s first look at what they have in common. From the hardware perspective, both are powered by MediaTek MT7688AN SOC featuring 802.11n Wi-Fi, 10/100M Ethernet connectivity and a MIPS 580MHz processor; both provide a USB host connector for linking with other USB devices and an SD card slot for expanding storage; and both platforms have 128MB DRAM and 32MB on-board flash which gives developers more resources for executing their applications.

From the software perspective, both platforms use OpenWrt (a Linux distribution) as the operating system providing a standard way to access the platforms; and a single firmware image providing a unified user experience in interacting with the systems. This means users don’t need to learn different operation flows across platforms whether it’s from the system configurations, basic operations or tool chain environments. This also simplifies migration from one platform to another. Furthermore, thanks to the sufficient DRAM, both platforms are capable of running Python and Node.js environments, which broadens the development possibilities of these platforms.

Now, let’s get back to the differences between the two platforms. The notable distinction, specification wise, is that MediaTek LinkIt Smart 7688 has an I2S interface for transmitting audio data, and the MediaTek LinkIt Smart 7688 Duo does not. On the other hand, MediaTek LinkIt Smart 7688 Duo supports ADC (Analog to Digital Converter) but MediaTek LinkIt Smart 7688 doesn’t.

However, what really sets these two platforms apart is the mechanism they use to connect with peripherals:

In MediaTek LinkIt Smart 7688, the peripheral related pin-outs such as I2C, PWM, SPI… etc. are connected to MT7688AN directly. Therefore these pins are controlled under the OpenWrt Linux system with API calls to UPM / MRAA. This means if you don’t need a real-time response from the peripheral controls, it might be good enough to use the MediaTek LinkIt Smart 7688 platform because it provides a single and capable system that utilizes the functionalities of MT7688AN to control peripheral sensors and modules.

linkit smart 7688 pinout 2LinkIt Smart 7688 pin-out diagram

In MediaTek LinkIt Smart 7688 Duo, the pin-outs for I2C, PWM, SPI, ADC… etc. are connected to the ATmega32U4 MCU. The nimbleness of the MCU system provides better peripheral responsiveness than the Linux-based system in MediaTek LinkIt Smart 7688. Moreover, the MCU is compatible with the Arduino development environment. This means you can use the Arduino IDE for programming and easily integrate sensors and modules with this MCU because many of the sensor and module drivers are already available in the Arduino ecosystem. In addition, applications running on the Linux side can communicate with the MCU through a UART port that connects the MT7688AN and the MCU.

pin linkit smart 7688duo
MediaTek LinkIt Smart 7688 Duo pin-out diagram

Finally, the important question “Which platform is right for me?” In most cases, MediaTek LinkIt Smart 7688 is generally capable of handling IoT applications like routers, connectivity gateways, IP cams, and any device that needs Wi-Fi connection, peripheral controls, and extensible USB with a compact and high level language-supported device. But for those of you who are familiar with the Arduino environment or who need more responsiveness and precision in the peripheral controls, MediaTek LinkIt Smart 7688 Duo provides a reference design showing how to integrate the MT7688AN SOC with the MCU system as well as how to utilize the features provided by the SOC.

We hope this article provided helpful information and wish you good luck in developing new and creative applications using MediaTek LinkIt Smart 7688. To get started go to the get started guide. For more inspiration, be sure to check out the community projects in the documentation.


This post is originally from MediaTek’s Blog.



About Author


March 2016