DIY a low-cost multi-functional dot matrix clock!

Hello everyone , Forward an article of mindfulness classmates

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Hello everyone , I am a ZhengN.

This time I reprint a nanny grade diy course ： be based on Esp8266 Multi function dot matrix clock .

brief introduction

I have known for a long time ESP8266 了 , At that time, I also used this to make some small demo, I never thought about getting some actual works out , Maybe it's because I compare dishes ！ Recently, I'm not so busy at work , Think about building a new one mqtt The server , Do some functions related to the Internet of things .

When browsing the forum, a post attracted me , It's this one ：

https://www.arduino.cn/thread-98790-1-1.html

Let me have the idea of making a lattice clock by myself , So I started the production journey of dot matrix clock bit by bit , The process is not difficult , But I also encountered many problems on the way , I encountered many problems on the way , Some have been solved , Some can only be solved simply and roughly , Fortunately, you can finally realize the functions you want .

Sum up experience and lessons and want to share them with people who have the same interests , Writing is not very good , The code is not well written , But still can't stop this sharing heart .

demonstration

picture

‍ video

https://www.bilibili.com/video/BV18i4y1R7ft?spm_id_from=333.999.0.0

idea

Although many people have done or are doing it on the Internet esp8266 Dot matrix clock , I repeat it more like building wheels , As a developer, I also resist the behavior of building wheels repeatedly .

But as a beginner, I want to experience the process of making wheels , And in this process, I hope this wheel has more personal thoughts in it , So I thought about starting this thing from scratch .

My personal idea is to make a simple lattice clock , In addition to having more other functions , To meet its core functions （ The clock , Low error ）, The second is to have more functions , Simpler interaction , Moreover, the cost should be low , Hope to think of yourself diy Of people use the lowest cost to make a beautiful and easy-to-use dot matrix clock .

• Simple

• To use

• Rich in functions

• Low cost

Hardware material

Here I will only introduce some necessary hardware , If you know everything, you don't need my little white list . Here I also put a Taobao store I've been shopping in ： Xinwei Electronic Technology .

It's not advertising , Mainly because the contents are relatively comprehensive , And the price is about the same , When buying things, you don't need to change between different Taobao stores , And the freight is only 3 element , Generally, the freight of this kind of electronic product store is 5-6 yuan . Please Baidu by yourself for the specific functions of components , I won't repeat them one by one .

NodeMcu(Esp8266)

This is our core hardware , A lot of function , It may be due to the rise in chip prices this year , Such things are becoming more and more expensive .

NodeMcu(Esp8266) Taobao pictures

DS3231

The main function of buying this module is not to reset the power down time , And the time error is small .

NodeMcu(Esp8266) Taobao pictures

Max7219 32x8 Lattice

There seem to be quite a few dot matrix driver chips ,Max7219 One advantage is that it can be cascaded .

NodeMcu(Esp8266) Taobao pictures

There are several DuPont lines

Buying DuPont line is to solve the trouble of welding , We can quickly and easily figure out the circuit we need

NodeMcu(Esp8266) Taobao pictures

Single touch module

It was originally a inching switch , But that kind of cost is not low , The experience is not good , So buy this kind of touch module , Used to realize click , double-click , Long press and other functions , Of course, this is unnecessary , If you don't want any entity interaction , Only small programs interact , You can ignore this module .

NodeMcu(Esp8266) Taobao pictures

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Clock function

Hardware functions

• NTP Timing

• Adjust the brightness

• Display time

• Show date

• Show the temperature

• Show B The number of fans standing

• Show custom content

• OTA to update

Wechat applet function

• Synchronize device status

• Set the display direction

• Set brightness

• Set whether to display

• Switch display content

• Switch display mode

• Return to factory

• wifi Distribution network

• OTA to update

• Customize lattice content

Schematic diagram

There is really no talent for drawing , There is no better mapping tool , Only with windows The self-contained drawing tool makes a simple and easy to understand schematic diagram , See forgiveness

Schematic diagram

• PS: Li Chuang PCB Schematic and PCB Planks are already on the way to production , With subsequent updates

The production process

In fact, the production process is simpler , It is mainly divided into the following steps

1. Purchase components

For purchasing equipment, please refer to some components mentioned above , Many Taobao stores on Taobao sell .

2.   Install the corresponding software

The software we mainly use here is arduino quite a lot diy Fans should have used , Used users can skip , You can also look down

install Arduino

Download via official website Arduino IDE, Unzip and run arduino.exe That means the installation is complete . The download address is as follows ：

https://downloads.arduino.cc/arduino-1.8.19-windows.zip

If the link fails , Please be there. Official website download , Download options Windows ZIP file

install esp8266 SDK

Here I also carry it directly from the Forum , But for the convenience of reading, it is listed below , You can directly follow the steps I listed , If you have any questions, please go to here See if there are other solutions

1. open Arduino IDE menu > file > Preferences , stay Add development board manager website In the input box , Fill in the following website ：https://www.arduino.cn/package_esp8266com_index.json

2. Download community packaged esp8266 Installation package , Just run it directly and decompress it

• SDK download （44M）：

  Blue cloud sharing address ：https://wwi.lanzouo.com/ij4GEyjcz7c   ( This is recommended )

  Alicloud disk address ：https://www.aliyundrive.com/s/QhgGreFTjJb ( This is recommended )

Double click Run to unzip , After decompression , And on again Arduino IDE, Can be in menu bar --> Tools --> Development board Find what you use esp8266 Development board

Tips ： If you have installed other versions esp8266sdk, Please delete first. , Reuse this installation package , Delete method ： Enter... In the file manager address field %LOCALAPPDATA%/Arduino15/packages, Enter by car , then Delete Drop some of them esp8266 Folder

Install serial driver

NodeMcu There are many specifications , It's common to see CP2102 Serial chip and CH340 Serial chip , Therefore, corresponding drivers are required , Here are the driver download addresses for both ：

CP2102 drive

Blue cloud sharing address ：https://wwi.lanzouo.com/iU5mcyjdxuj ( This is recommended )

Blog file address ：CP210x_Universal_Windows_Driver.zip（ I don't recommend this , If the above link fails, you can use ）

CH340 drive

Blue cloud sharing address ：https://wwi.lanzouo.com/iyFTayjdxsh ( This is recommended )

Blog file address ：CH34x_Install_Windows_v3_4.zip （ I don't recommend this , If the above link fails, you can use ）

• Decompress the corresponding driver package , Then double click the driver of the corresponding system .

• After the driver is installed successfully, you need to restart the computer

3. Connect the corresponding wire

Here is a simple connection using DuPont line , If there is a big man willing, you can also weld through the circuit diagram I draw , However, it is recommended to use DuPont cable connection first , Conduct welding treatment after debugging the program .

NodeMcu and Max7219 Lattice connection

• VCC → 3.3V ( In fact, you can also connect here 5v, If you want the brightness of the lattice to be brighter )

• GND → GND

• DIN → D7

• CS  → D6

• CLK → D5

NodeMcu and DS3231 modular connection

• VCC → 3.3V ( Don't answer here 5v, Low voltage is safer )

• GND → GND

• DIN →  D7

• SDA  → D2

• SCL →  D1

NodeMcu and Single touch module connection

• VCC → 3.3V ( Don't answer here 5v, Low voltage is safer )

• GND → GND

• SIG  → D8

4. Write program

Use Arduino The writing program is actually quite simple , The general steps are divided into the following steps

Check

• Simple ESP8266SDK Is the installation successful

• Check whether the serial port driver is successfully installed

Install the required dependency packages

• Because I'm also a beginner , Many use other people's library files , I didn't go deep into the principle to rewrite the code , So we need to install some library files

• The installation steps are as follows ：

  • Tools --> Management of the library --> Search the libraries we need to install --> Click Install

• The library files to be installed are as follows

  • DS3231 DS3231 Clock ready-made library file

  • LedControl drive Max7219 Lattice library file

  • OneButton Realize key click , double-click , Long press function library

• If there is a missing Library , Please read the error message , Press the error prompt to install the Library

Download the source code

• github download https://github.com/Lengff/esp8266-lattice-clock-open

• gitee download https://gitee.com/lengff/esp8266-lattice-clock-open

  Download our source code through the above address .

Write source code to Esp8266

• adopt Arduino IDE Open the code we downloaded in the previous step

  file --> open --> Select the folder where the source code is located .ino Postfix file

• Choose development board

  Tools --> Development board --> ESP8266 --> NodeMcu 1.0

  
  Choose development board

• Select port

  Tools --> port --> Select the port corresponding to our serial port device

• Write program

  project --> Upload or Point left → arrow （ Baud rate is selected 115200, It's going to be faster ）

5. test & test

Here are many problems encountered in personal processing ：

1. Program compilation failed

• The most likely reason for compilation failure is that the library file does not exist , perhaps esp8266 Of sdk There is a problem with the installation , Just check the compilation error

Program upload failed

• Upload failure basically means that the serial port is not selected correctly or the development board is not selected correctly

After uploading successfully, there is no display

• Here you need to check whether your wiring is correct .（ Please disconnect the power supply before doing this ）

One click distribution is unsuccessful

• The distribution network requires mobile phones and devices to be in the same wifi, And wifi yes 2.4G Of wifi

• Check the dot matrix display ：no wifi Indicates that... Has not been configured wifi, Need configuration wifi;con wifi It means that wifi Information. , on connection wifi, If you need to reconfigure wifi You need to press and hold the touch button 6 Seconds to reset the system .

• It is suggested to press nodeMcu Upper reset Key , Then click the distribution network on the mobile phone

The content displayed after the distribution network is successful is 23:59:59

• This means your DS3231 There's something wrong with the wiring , It is necessary to check whether the wiring is correct .（ Please disconnect the power supply before doing this ）

• If it doesn't work , Please disconnect the power first , then DS3231 Remove the battery on , Try again after reinstallation .

Interaction

On the hardware, we set up a touch button for human-computer interaction , I implement more interactive logic on small programs .

Touch the button ：

• single click ： Click to switch the display function , At present, it is Time - date - temperature - B The number of fans standing - Custom display Five cycle switching

• double-click ： Double click to switch the display mode of the function , for example ： There are two display modes of time 1. when - branch - second  2. when - branch Two different display modes can be realized

• Long press for three seconds ： Long press for more than three seconds and less than six seconds will trigger NTP Auto calibration time

• Long press for six seconds ： Long press for more than six seconds will reset the system （ When the system is abnormal , Or replace wifi The system needs to be reset ）

Wechat applet ：

• I won't go over it here , The functions of wechat applet are relatively simple and clear. You can see it at a glance , All the functions supported by the above keys are supported by wechat applets

Applet

Why do you choose applets to interact with Esp8266 Interaction ？

1. Small programs are relatively fast to develop , There are many functions supported , Many functions are called directly api that will do

2. Use app Or visit esp8266 I think the interaction of the pages inside is a little poor , I think the most interaction should be simple , There is no need to have too much learning cost

3. The applet supports distribution network ,UDP, Bluetooth and many other functions , Other subsequent small works may use small programs

The page display

Screenshot of applet page

Code

At present, the applet is not in this open source sharing , In fact, small programs are not difficult , And it can be used directly , Reduce everyone's development work .

Applet entry

Scan the following applet code through wechat or Wechat search applet Lengff You can find my applet

Screenshot of applet page

Communication mode

at present esp8266 The communication with applet is using UDP The way of communication , Use UDP The advantage of the communication method is that there is no connection , Open and use , There is no need for a server .

Just promise esp8266 The same LAN is connected to the mobile phone , And you can find devices by broadcasting , There is no need to establish long links , The disadvantage is instability , Loss of package , But I think it is acceptable , Because mobile phones send more instructions , Every time I send instructions twice, the probability of packet loss will decrease .

Transfer protocol

udp Is to send some hex Data packets esp8266 Data transmission with mobile phones , So I simply defined my own UDP Transfer protocol , Agreement as follows ：

 Customize a UPD Protocols are used for applets and esp8266 Conduct UDP signal communication 

|0 1|2 3 4 5|6 7|0 1 2 3 4 5 6 7|  
---------------------------------
|RT |TE     |VN | LH            |
---------------------------------
 Message data  (64bit)
---------------------------------

 Customize UDP Agreement that :

1. RT: (2bit) Successful return value 
2. TE: (4bit)type Message type : 0:  reset time  ,1:  Set brightness  ,2:  Switch function  ,3:  Switch function display style  ,4:  subscribe BIlibiliUID ,5:  Whether to enable dot matrix screen  ,6:  Switch the display direction  ,7:  Set user data  ,8:  Set animation speed  ,9: OTA  upgrade  ( There's a flaw here , It only supports 16 Types , So we will expand here later )
3. VN: (2bit)version Protocol version , It's fixed at present as 1
4. LH: (8bit)length Packet length 
5.  Message data : (64)bit  edition 1 The maximum packet length currently supported is 64bit

Optimize ？

Optimization space is natural , In fact, the change is not big , That is the subsequent access to their own MQTT The server is compatible UPD Communication mode , But at present, there is no stable and available server , Blind access and subsequent upgrading will affect the normal function of the device .

Self evaluation

This project （ It's also a small project ） I did it for more than a month , It can't be regarded as from 0 Start , At first, I will be familiar with something , Only the knowledge points are scattered , It's like a messy puzzle , This time it's like a jigsaw puzzle .

Although it's not spelled well, it's also a work spelled out at least , Although many people make this kind of dot matrix clock , But I personally feel that if I really practice, I will find it is not so simple , And you may not be satisfied with what others do , Do it by yourself, and you can inject your soul into it .

Here is my personal feeling ： I am not full-time engaged in this kind of hardware development , This is just a personal hobby , Although I usually accumulate some relevant knowledge , But it is far less efficient than systematic learning .

So if you really want to learn this, you should systematically watch some videos to learn , The second is practice , Although I have mastered some scattered skills , But I don't know how to use , So you need to practice constantly to understand your skills .

shortcoming :

• Connection required wifi（ And it must be 2.4Gwifi） Ability to use -（ This will also be optimized in the subsequent procedures ）

• Continuous power supply is required , Because lattice power consumption is relatively large , So the experience of using battery is very poor

advantage

• Support OTA Sustainable renewal system

• The interaction is simple and convenient

• Support customized display content

ending

Here I offer a 8x8 and 32x8 Dot matrix online mold tool , It's rough , If you need to improve, please leave a message in the comment area .

8x8 Dot matrix online mold tool ：http://lengff.com/lengff/lattice2.html 32x8 Dot matrix online mold tool ：http://lengff.com/lengff/lattice3.html

reminder

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