This article briefly describes the Mediatek Linkit 7688 and 7688 Duo development boards. Below the links for the two boards
The specifications of the two boards are the following
Linkit 7688
| Model | Linkit Smart 7688 |
| MPU | MT7688AN, MIPS24KEc, 580MHz |
| RAM | 128 Mb DDR2 |
| Flash memory | 32 Mb |
| GPIO | 22 (MT7688AN) 3,3 V |
| PWM | 4 (MT7688AN) 3,3 V |
| Expernal Interrupts | 22 (MT7688AN) |
| SPI | 1 (MT7688AN) |
| UART Lite | 3 (MT7688AN) |
| Power | Micro USB 5V DC or PIN 3,3 V |
| USB HOST | Micro USB |
| Ethernet | By extension |
| Wifi | 1T1R 802.11 b/g/n (2.4G) |
| User storare | Micro SDSDXC sdcard |
| Dimensions | 55.7 x 26 mm |
| Weight | 39 grams |
Linkit 7688 Duo
| Model | Linkit Smart 7688 Duo |
| MPU | MT7688AN, MIPS24KEc, 580MHz |
| MCU | Atmel AVR 8MHz |
| RAM | 128 Mb DDR2 |
| Flash memory | 32 Mb |
| GPIO | 3 (MT7688AN) 3,3 V 24 (ATmega32U4) |
| PWM | 8 (ATmega32U4) 3,3 V |
| External Interrupts | 8 (ATmega32U4) |
| SPI | 1 (ATmega32U4) |
| UART Lite | 1 (ATmega32U4) 1 (MT7688AN) |
| Power | Micro USB 5V DC or PIN 3,3 V |
| USB HOST | Micro USB |
| Ethernet | By extension |
| Wifi | 1T1R 802.11 b/g/n (2.4G) |
| User storage | Micro SDSDXC sdcard |
| Dimensions | 55.7 x 26 mm |
| Weight | 39 grams |
The two boards share the same Microprocessor (MPU MT7688AN), but in the case of the Linkit 7688 Duo this MPU is supported by the Atmel Microcontroller (MCU ATmega32U4) for device management.
The interfacing schemes are shown with peripherals in the two cases below
The operating system used for both bords is OpenWrt, but the peripherals management is different. While in the case of Linkit 7688 we only rely on MPUs and specific libraries to manage the interfacing with peripherals, for the Linkit 7688 Duo the ATmega32U4 microcontroller manages the peripherals. The programming of the ATmega32U4 is executed with the Arduino IDE by adding the Linkit 7688 Duo board support into the tool as specified at the following link
Arduino Ide support for Linkit 7688 Duo
At the followning link there is the Mediatek documentation for the two boards
Linkit 7688 and 7688 Duo Resources
The following pages show how the two boards can interact with the various peripherals
At the Mediatek site, there are also examples to follow step by step to test the various features of the development boards.
The next article shows how to connect the USB OTG cable , to use with a USB drive, an USB TTL serial cable, to monitor the device, to the board