Monthly Archives: November 2014

VoCore: Simple Start Tutorial 2

1. USB wire 
2. VoCore

Step 1:
Cut the USB wire in the middle. We use red and black wires.

Clean up the USB wire.(not necessary).Tape again. :)

Step 2:
Connect VoCore to the wire, and connect USB to computer.

Now it works, then you can find VoCore in your computer AP list.
Rest please read

1. Some computers USB power supply is not stable, that might cause VoCore failed to reboot. MacBook, ThinkPad do not have such issue. From report, some Dell PC might have such issue.
2. Clean up is not necessary, but better to do if you want to use your USB wire in long term. :)

VoCore: Simple Start Tutorial 1


1. VoCore
2. 18650 battery(Li)
3. Two wires

18650 battery voltage should be higher than 3.60V.

Step 1:
Connect the wire to VoCore.

Step 2:
Connect the wire to battery

Step 3:
It works

Step 4:
Wait about 30 second, you will find VoCore in your wifi AP list.
Connect to it.
Screen Shot 2014-11-06 at 10.38.33 pm

Step 5:
ssh root@, password: vocore
Now you are ready to use it.
Screen Shot 2014-11-06 at 10.39.06 pm

1. VoCore need a very stable input power, or it will fail to boot. (I found when the wifi start up, the momentary current is high, about 350mA~400mA, so if the input power do not have such ability to supply, it will reboot)
2. I use tape to make GND touch the battery negative pole, that is not a good idea, just temp solution, better to use a battery holder, and solder wire to it, to make sure it is well connected.

VoCore: Mountain of Packages, moved

This should be the final step of the indiegogo campaign. Just record what is happening from last week.
Not that smoothly as always. πŸ™‚

1. Post office package the packages takes 3 days
I thought that should be all of the shipment, so I make an update on indiegogo.
Just put them into bags, and put the connectors with the items together.

2. Post office tag the packages takes 3 days
We have the trace id, but in fact, the package still in post office.
Every package be weighed, also check the address, pick out the one have special characters.

3. Post office input the trace id into their system takes 2 days.
Finally I get the trace information, the package are shipped.
I have checked some of the package, all have information already, so I just make another update yesterday, that is the trouble comes πŸ™‚ I get tons of email about the trace id still no information(The post office still not make all the package information online) and someone complains need password to login, also some warm heart emails, really appreciate for that, I can not reply one by one but I have read them all.

Ye, after that, I remember I am sending email to thousands of people…I do not dare to use that update anymore πŸ™‚

(Email should input into the red box, some browsers might not compatible, due to this part I write by C++ for faster speed)
Screen Shot 2014-11-06 at 8.12.32 am

At least VoCore are shipped almost in time(how stupid I am, I thought I can ship them earlier, this is true: it is always hard to do than think)
I also take a look on other indiegogo campaign, do not how much stress they are taking, some of them delayed almost a year…

VoCore: Wifi Toy Car

Just finish the shipping πŸ™‚
Have some time to public my test project.

To make a toy car, we need some materials:

1. a toy car base, include wheels, motors.
2. batteries, they areΒ two cheap 18650(the real cap is 800mA…)
3. a driver board, itΒ is L298N.
4. vocore, of course(do not need dock, but with dock assemble will be easy)
5. some wires.

assembled base:


Rest, you need a computer, better to be a linux system(virtual machine is also good), already install and compiled openwrt, we need its cross compiler.(RT5350 SDK complier is also fine, but that is hard to find. I like openwrt one)

For remote control, you might need an android device or iOS device, I write a simple code based on Qt, just UDP protocol.


L298N have two motors control and one 5V voltage output.
We just connect the 5V to vocore USB power slot(or the 3.5V~6V hole without dock), I cut a usb wire.

Connect L298N control with VoCore GPIOs. Six control ports, so we need six gpios.

ENA-> enable motor A
ENB-> enable motor B
IN1, IN2 -> control motor A
IN3, IN4 -> control motor B

Checking DTS, the dear VoCore have GPIO21~GPIO26, totally 6 GPIOs exported already, so just use them.
IN1-> GPIO23
IN2-> GPIO24
IN3-> GPIO25
IN4-> GPIO26



Better to cover here, or it might short connect.

Now boot VoCore. Push the button πŸ˜‰ It is not necessary if you do not have a switch.

Set all GPIOs to output and all GPIO to 0.
Set Enable A to 1.
Reference: Test GPIO


Now there is a stupid video πŸ™‚ I make one wheel run. It drop down from my table but still run in a cycle, look like the VoCore quality is not bad. Just wake up my dog…:D

Tomorrow I will write a simple application on my phone, so it will be enable the remote phone control πŸ™‚

Let’s Talk About Hardware Design

Today I find some interesting, my android test phone: a white XiaoMi4 can not read SIM. I am using it to communicate with VoCore through GSM/3G/4G internet to test Cloud service( will public later πŸ™‚ ), so I change SIM card frequently. Unfortunately, this new phone, after about several times SIM plug in/plug out, it can not read SIM anymore.

This is the XiaoMi phone:

This is my old test phone:

This is iPhone6

Can you find the difference?
iPhone 6 and my old test phone SIM card metal pads are at bottom once installed, but XiaoMi is at top. So if your plug in/plug out some more, once the SIM card is not that flat, it will broken the phone’s SIM pin.

From this small issue, we know, hardware design is an true art. Every detail must consider carefully. Apple is really good at this πŸ™‚ XiaoMi copy the surface, but not the inside…shame.