VoCore: Returned Package 1

Here are some packages returned from China Post, please check if there is your package. Most of them are incorrect address. (After 4~6 months, some people might already move to new place). If your trace id is in the list, please email your new address to support@vocore.io.


VoCore: StarterKit Breakout Board

VoCore breakout board will have such features:

1. two ethernet ports.
2. jtag port, 2.54mm pins, with 10k ohm pull up resistors.
3. gpio port, 2.54mm pins, with 4.7k ohm pull up resistors.(some for boot stripe has pull down)
4. reset button.(with 4.7k ohm pull up)
5. spi port, 2.54mm pins.
6. micro USB power in.
7. uart full port, 2.54mm pins.
8. usb 2.0.
9. size about 6cm x 4cm

consider to add to this breakout board:
1. arduino chip and pins export.
2. on board usb2ttl chip.

Former layout:

VoCore: wireless printer & usbip

Plan to use usbip upgrade my cheap printer(Epson ME350) into a wireless printer, also a wireless scanner.
But just find it is very hard to complete that.

There is kmod-usbip-client, kmod-usbip-server in the openwrt truck, but I just can not find usbipd, that is a important compose for transfer data to client computer. As I remember, it is there in old openwrt truck…

If I can not find any exist package, I have to rewrite part of that usbipd, to make it work.
usbipd is based on glibc…but current openwrt is using ulibc, can not compile directly.
Only this middle adapter application missed…I am so eager to try usbip control my printer wirelessly. :)

VoCore: MJPG Camera

1. necessary library(openwrt must have video support)
(if you do not know how to compile it, download here packages):

copy all of them to vocore:
scp kmod-video-core_3.14.25-1_ramips_24kec.ipk root@
scp kmod-video-videobuf2_3.14.25-1_ramips_24kec.ipk root@
scp kmod-video-uvc_3.14.25-1_ramips_24kec.ipk root@
scp libjpeg_9a-1_ramips_24kec.ipk root@
scp mjpg-streamer_r182-2_ramips_24kec.ipk root@

ssh to vocore, install:
opkg install /tmp/kmod-video-core_3.14.25-1_ramips_24kec.ipk
opkg install /tmp/kmod-video-videobuf2_3.14.25-1_ramips_24kec.ipk
opkg install /tmp/kmod-video-uvc_3.14.25-1_ramips_24kec.ipk
opkg install /tmp/libjpeg_9a-1_ramips_24kec.ipk
opkg install /tmp/mjpg-streamer_r182-2_ramips_24kec.ipk

2. one usb mjpg camera. mine get from taobao.com, cost about 12USD.

3.a vocore, need to connect with USB D+/D- and give the webcam 5V power.
3.b vocore + dock, this is much easier, directly connect to dock usb port.

Now, run mjpg-streamer
/usr/bin/mjpg_streamer -i “input_uvc.so -d /dev/video0 -resolution 320×240″ -o “output_http.so -www /www
(Note: “/etc/init.d/mjpg-streamer start” not working, have to call it directly)
Screen Shot 2014-12-06 at 6.01.35 PM

Try with your browser :) Plan to write a plugin for vohttpd, to make this easier.

Looks like my webcam is a little short sight…

VoCore: SPI & MicroSD 12

Finally it works :) But still not perfect.
Thanks for noltari find the problem. Just change spi speed line in dts, then it works.

Here is the patch and new spi-rt2880.c(rewrite by noltari)

Here is the screen capture.
Screen Shot 2014-12-04 at 5.46.30 PM

PS: here is the patch of VoCoreopenwrt-vocore patch
1. change ap to VoCore to avoid ap name conflict with other openwrt device.
2. change default ip to to avoid ap+sta mode ip conflict.
3. change shadow file, so there is default password “vocore”
4. change dts flash partition to fit 16MB flash.(keep the line if you are using 8MB version vocore)

Here is the link of compiled firmware: vocore.16m.microsd.bin

vohttpd: light weight embeded httpd

VoCore Web Server change its name to vohttpd.
A former version has released and put into GitHub: https://github.com/vonger/vohttpd
My target is to make a httpd who has faster speed and less resource consume, the most important, it should be flexible, easy to add plugins.

vohttpd should be a basic core do not contains any unnecessary features, its main target is to provide an environment for plugins. Any features could be move to plugins and they should not appear in the core application.

Plugins are the most important part. For example, if I want to have a browser based user interface for gpio control(as my last blog shows), I just write a plugin and use vohttpd API to load that plugin, then it will be OK to use. If I connect VoCore to a mjpeg webcam, I can get picture directly from browser, do not have to code a middle adapter.
Future, we can add more javascript for the client side, just draw&drop the plugin into the browser, all function will be automatic load to VoCore, that will be cool.

Super simple, and born to be cross platform. :)

For now, load/unload/query plugins feature has done. In source code, there are two example plugins, one for test, one for online plugin control, such as upload plugin or remove plugin.


There are a lot of work left to do:
1. use mmap for better memory usage when receiving big file.
2. add https as an option.
3. add auth function. (But make it as plugin? or make it into vohttpd?)

I am glad to hear from you. Please leave a comment.

PS: I spend time on this project just because I really need something like this for my further use, and the development process is very interesting. :) I do not intend to replace any exists httpd, such as LuCI, uhttpd etc. They are very good too.

VoCore: Package FAQ

There are mainly two type of packages:

1. VoCore, main board version
a) 4x4p female connectors.
b) 4x7p female connectors.
c) USB convert to TTL, driver PL2302.

VoCore + Dock
2. VoCore + Dock
a) 1x4p female connectors.
b) 3x7p female connectors.
c) USB convert to TTL, driver PL2302.

What are those addition female connectors used to do?
They are used to solder on the pin holes to make them stand longer.
1.27mm female connectors are hard to find in some countries, so I add that to the package, but that is not necessary at all. From current report, the female connectors did not help much, just lead a few people broken down VoCore when they trying to solder the connectors. I am thinking to remove it in further package.
For beginner, a break out board is necessary, so people will not afraid of broken their little VoCore. :) I am on that now.

PS: I thought the buyers of VoCore should have enough skill to solder that, but I am totally wrong. That’s my bad. :)

What is that USB2TTL used to do?
That USB2TTL is very important. It helps you repair the bricked VoCore by uboot or connect to VoCore when your wifi or ethernet do not work.
When I write driver for VoCore, I always make stupid mistake, such as system can not reboot or too heavy CPU load, make the wifi can not work normal. For such situation, USB2TTL is the only way to connect to VoCore(maybe JTAG is fine too, but I did not try).

Next version I will consider to add USB2TTL chip to dock, but the space on dock is so limited, that QFN chip + slot parts is not easy to assemble.
This move must be very careful :)

How to detach the VoCore and the Dock?
That is not easy, due to there are almost 20 pins tightly connected together and the pin are long, 14mm, easy to bend.
There is no glue between the VoCore main board and the dock, the white one is just silicone grease make the CPU well touch the ethernet port which is used to be a heat sink.

Detach the VoCore + Dock, two keywords are “vertical” and “slow”, the pin into the female connector about 1.4mm, if you do not do it vertical, the pin might bend.


VoCore: Starter Tutorial Part2

IMG_0196 (1)

About GPIO, I post a blog when I start VoCore.
Please check this link http://vonger.cn/?p=473.

There is some note about how to finish this:


Screen Shot 2014-11-21 at 7.03.13 PM

That 330ohm resistor is necessary, without it, the LED will burn.

Already in this post http://vonger.cn/?p=473.


We can write an API for this LED control, so we can simply control it from browser remotely :) phone, computer, pad, anything have broswer.

Here is the code, based on VoWeb, just add one function:

int voweb_func_gpio0ctrl(socket_data *d, string_reference *pa)
    char buf[MESSAGE_SIZE] = "Invalid parameter.";
    FILE *fp;

    fp = fopen("/sys/class/gpio/gpio0/direction", "w");
    if(fp == NULL) {
        sprintf(buf, "update gpio 0 direction failed.");
        return send(d->sock, buf, strlen(buf), 0);
    fwrite("out", 1, 4, fp);

    if(memcmp(pa->ref, "on", 2) == 0) {
        fp = fopen("/sys/class/gpio/gpio0/value", "w");
        if(fp != NULL) {
            fwrite("1", 1, 2, fp);

            sprintf(buf, "update gpio 0 value to 1 success.");
        } else {
            sprintf(buf, "update gpio 0 value to 1 failed.");
    if(memcmp(pa->ref, "off", 3) == 0) {
        fp = fopen("/sys/class/gpio/gpio0/value", "w");
        if(fp != NULL) {
            fwrite("0", 1, 2, fp);

            sprintf(buf, "update gpio 0 value to 0 success.");
        } else {
            sprintf(buf, "update gpio 0 value to 0 failed.");

    return send(d->sock, buf, strlen(buf), 0);

And register this function:

string_hash_set(funcs, "gpio0ctrl", (uchar *)voweb_func_gpio0ctrl);

Here is compiled one and necessary html: download

Uncompress vocore.voweb.gpio.test.zip to local folder, such as “~/voweb.gpio”, and scp all of the files to root@

scp -r ~/voweb.gpio/* root@

Then run command in vocore.

/root/voweb 8080 /root/html

Just open, you will find this page, now, just click on the switch, the LED is under your control.

Here is a simple video:

Any questions, just leave a comment under. :)
brandonhead, I like your question :D

vonger.cn: Speed Up

There are many people in China report issue to me, my blog is very hard to open, today I find the problem finally…
WordPress load google fonts at head part, but in China the Great Firewall block all google address. So the load process is very very very slow.

Get the bad code in /var/www/html

find . | xargs grep 'fonts.google' 2> /dev/null:

Comment all of them, now the user from China or other country blocked google can view it much much faster :)

VoCore: No LuCI 3

From last week, I am thinking of a super light weight web server.
There are many choices:
LuCI + uhttpd, goahead, mini-httpd, etc…

But none of them is perfect for me:

1. cgi part use too much resource.
Fork new child process to deal cgi, and dealing code with Lua. Calling script to create the html page. If I need update frequently, such as video, the board will die for out of memory or cpu 100%.

2. memory control low efficiency.
They call malloc for every memory request. For small memory device, such malloc is pain. It will generate tons of memory fragment, and the core have to arrange them, costs lots of resource.

3. unnecessary optimisation.
We just has one core, so whatever the optimisation you do, remember the most effect way is to make the app run in one thread.
Such on board web server do not have to deal with many people request same time, so use why use pthread? Looks like the reply time is shorter, but underground it costs two times of CPU time, if the load is heavy, it is twice slower.

4. take too much disk(flash) space.
goahead, after I compile it, the size goes to 850KB, and even not contains its dependency library.

So same reason as I make VoCore, I write something looks better to me.

1. advanced memory control.
Only 12KB or even lower memory request. Self maintain memory, do not create memory fragment.

2. optimisation for one core cpu.
The full application only have just one thread, no switch cost.

3. cgi write in pure C code.
This makes it more effective, no middle layer. Pure server, client mode.

4. super fast.
deal 60~80/sec request on VoCore.

5. minimised dependency
Only basic C library is necessary. Do not need pthread, libdl, etc.

6. small executable file size.
After compile, it is 33KB, and do not need addition library. That’s all.

7. source code in one file.
I like sqlite3 style, so I make all files into one file, easy to compile.

This VoWebServer is very “embed”, of course, it is just a new project, many bugs have to be fixed, at least, we have one more choice. :)

Here is the source code, once I feel happy about it, will upload to github.
compile it by one line:

cc -g voweb.c -o voweb

Compiled one for VoCore: voweb

run it like this:(put some htmls to /var/www/html, it will get index.html)

voweb 8080 /var/www/html

Then open, you will find the page :)
Test cgi function:
(cgi-bin folder do not exists)