Breakout for LinkIt Smart 7688 v2.0

Breakout for LinkIt Smart 7688 v2.0 is a Grove port integrated expansion board for LinkItTM Smart 7688 development board. This breakout board will save a lot of work and makes prototyping easier through simplified wiring. It will assist a beginner to get started fast. It supports serial buses like I2C, UART. It comes with USB, Ethernet, and 3.5mm Audio ports.

Version Tracker

Product reversion

Release date

Support status

Notes

Breakout for LinkIt Smart 7688(v1.0)

November 2015

Supported

None

Version 2.0

April 2016

Supported

New features:

Support recording functionality
For 3.5 mm phone connector (audio jack), it supports the protocol OMTP and CTIA. You can use either protocol by switching a switch. About how to switch protocol, we will describe it later.

Features

Grove interface makes wiring easier and allows expansions with Grove modules.
USB host
Audio Output
Ethernet port
Cost-effective

Application ideas

IoT/Gateway Device.
Robotics
Smart multimedia devices
Teaching and learning

Specification

Input voltage	5.0V(With USB Power port)
Operating voltage	3.3V
Debug port	1(Quantity)
Ethernet port	1(Quantity)
USB type-A	1(Quantity)
Headset port	1(Quantity)
Note Debug pins, Ethernet pins and USB type-A host pins connect with MT7688, other pins connect with ATmega32U4.

Hardware Overview

Grove interface: Connect rich Grove interfaced functional modules. With this kind of ports, you never need jumper wire or soldering work, and you can make more powerful applications with those functional modules.

To switch phone connector protocol between OMTP and CTIA

In preceded figure, you can notice that there are six pins and two jumper caps on bottom-right corner. These pins are used to switch phone connector protocol. As you set tiny jumper(both) to left-four pin, protocol OMTP is used. As you set tiny jumper(both) to right-four pin (as preceded figure shows), protocol CTIA is used. As following figures show:

Note that to use the recording functionality, you need to update on-board firmware to Breakout for LinkIt Smart 7688 firmware(above version v0.9.2).

Note that we recommend you use external storage device, because the Write/Read speed of on-board flash memory is limited.

Parts list

Parts name	Quantity
Breakout for LinkIt Smart 7688 v2.0	1PCS

Get started

Material required

LinkIt Smart 7688 × 1
USB cable (type A to micro type-B) × 2
USB to Serial adapter × 1
Jumper wires × 3
Stereo (with 3.5 mm audio cable) × 1
USB flash driver (with audio file of MP3 format inside) × 1

Play music

1. Refer here to connect your LinkIt Smart 7688 to Internet.

Note that you can plug jumper wires to MT7688 UART2 port instead soldering them to Pin 8, Pin 9 and Pin GND.

Note that in rare cases, you might not connect to Internet successfully, reboot the embedded OS.

2. Open a console with USB to Serial adapter.

3. Connect all parts like follows:

Note this is a figure of Breakout for LinkIt Smart 7688(v1.0).

4. Enter folder of USB by type cd /Media/USB-A1 in console.

5. Play music with utility Madplay(installed on OpenWRT) by typing madplay filename.mp3 into console.

6. Now you will hear the music.

Resources

Schematic files
LinkIt smart 7688
OpenWrt
Link to buy a LinkIt Smart 7688.