Feature image from Arduino - LED - Blink | Arduino Tutorial - Arduino Getting Started (Searched by arduino blink led experiment in DDG )

Burn LED

(2024-10-28)

• I broke an LED because I connected the LED directly with 3.3 V without using a current-limiting resistor.

  • A typical current through an LED is

Blink Nano

Can’t Upload

References:

1. 电子教学 - 【教学】Arduino上传失败的24种解决方法 - bilibili - joyspace
   • Searched by Arduino烧录失败 in bilibili
2. avrdude: ser_open (): can’t open device “\.\COM4”: acces denied
   • Searched by avrdude: ser_open(): can't open device "\\.\COM4": Access is denied. in DDG
3. CH340 Windows 10 driver download | arduined.eu
   • Searched by Arduino Nano CH340 in DDG
4. Uploading a simple sketch takes forever - arduino uno - SE
   • Searched by arduino IDE uploading long time in DDG

(2024-10-29)

Problem: Cannot upload firmware to board: Arduino Nano

• Hardware connection: Plug USB cable barely between the Nano board and laptop.

  

• Board and Channel selection:

  

1. My own sketch cannot be uploaded to board.

   The “Uploading” reminder hangs forever, and finally the following errors prompted:

   

   1 2 3 4 5 6 7 8 9

   Sketch uses 924 bytes (3%) of program storage space. Maximum is 30720 bytes. Global variables use 9 bytes (0%) of dynamic memory, leaving 2039 bytes for local variables. Maximum is 2048 bytes. avrdude: stk500_recv(): programmer is not responding avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0xaa avrdude: stk500_recv(): programmer is not responding avrdude: stk500_getsync() attempt 2 of 10: not in sync: resp=0xaa ... # repeated messages avrdude: stk500_recv(): programmer is not responding avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0xaa

2. The official example (‘File’ -> ‘Examples’ -> ‘01.Basics’ -> ‘Blink’) cannot be uploaded either

   1	avrdude: ser_open(): can't open device "\\.\COM4": Access is denied.

3. ‘Serial Plotter’ and ‘Serial Monitor’ both don’t return anything. Sometimes, it showed ‘Not connected. Select a board and a port to connect automatically.’.

   

Adressing

1. Install driver for CH340 chip.

   • Reasons

     1. Someone mentioned this driver in his question (r2-Forum).

     2. Video mentioned this chip (r1-bili).

        • My Nano board does have this chip.

          Back	Front

     3. Kaushik mentioned that maybe I dont have the correct driver installed.

   • Actions:

     1. I checked the driver in ‘Device Manager’ before installation (r3-eu), and found it had been installed:

        

   • Results:

     1. I didn’t install the driver right away, becaues I also noticed NoMachine (remote desktop) also use USB.

   • Analysis: Maybe the NoMachine occupies some resources?

2. Close the remote connection of NoMachine.

   • Results:
     1. After relaunching the Arduino IDE, the ‘Uplong’ still can’t complete.

3. Try to Update the driver, as suggested by (r3-eu)

   • Actions:

     1. Click “Update”

        

   • Results:

     1. It’s already installed:

        

4. Install the driver again by using CH341SER\SETUP.EXE

   

   • Results:

     1. Failed:

        

5. Quit NoMachine first, then install SETUP.EXE:

   • Actions:

     1. Quit NoMachine service:

        Tray menu	Confirm quit

   • Results:

     1. Driver installation still failed.

6. Uninstall NoMachine and restart the laptop.

   • Actions:

     1. Check the ports. There is only one port: COM3

        

   • Results:

     1. Cannot upload the firmware.

7. Plug the cable into the other USB slot, whose index is COM5:

   • Actions:

     1. Plug into another USB

        

   • Results:

     1. Doesn’t work either.

8. Reinstall the driver SETUP.EXE,

   • Results:

     1.No luck: “Driver install failure!” persists.

9. Select another processor: ATmega328P (Old Bootloader) instead of ATmega328P

   • Reasons:

     1. Glipsed an answer that mentioned to use the old version (r4-SE)

     2. The combination of my previous trials is:

        

   • Results:

     1. It works!

        

     2. The driver apperas again automatically, though I didn’t install it manually.

        

   • Conclusion:

     1. The problem is not the CH340 driver, but the processor.

LED Chaser

References:

1. Arduino基础课程01——初始Arduino - bilibili - funcodecc

   • Directed by Arduino基础课程09——SPI通信

2. Arduino Tutorial: LED Sequential Control- Beginner Project - YouTube - Drone How

   • Searched by arduino experiments flowing led in Google video

Materials:

1. Recite the code after the first watch:

   1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29

   void setup() { pinLed[] = {1,2,3,4}; // Indices of pins to be used numLed = 4 // Configure pins // Specify Mode for pins: INPUT or OUTPUT // Set every pin to OUTPUT to drive an LED for {i=1, i<=numLed, i++} { pinMode(pinLed[i], 'OUTPUT'); // Input 2 args: pin id and mode } } void loop() { for{i=0; i<=numLed; i++} { digitalWrite(pinLed[i], HIGH); // Two levels of voltages delay(500); // ms digitalWrite(pinLed[i], LOW); } for{i=numLed, i>0; i--} { digitalWrite(pinLed[i], HIGH); delay(500); digitalWrite(pinLed[i], LOW) } }

   My Mistakes:

   1. OUTPUT as a pinMode seems to be a global variable, NOT a string.

   2. Data types are missed when create a variable: int numLed = 4.

   3. The pin-1 of UNO cannot be set as OUTPUT? The pins used are started from pin-2: int pinLed[] = [2,3,4,5]

   4. The arguments of syntax for are separated by ; and enclosed by parentheses ( ), not curly braces. And the temporary counter i also needs declaration of data type.

   5. i is the index of the array, ranging from 0-3.

   6. Don’t forget semicolons at the end of each line;

   7. Variables used both by setup() and loop(), i.e., numLed and pinLed should be declared outside of these functions.

   8. Don’t forget current-limit resistor. There is a warning from the simulation platform (funcode.cc): “The maximum current allowed by led-node is: 0.02”

• Rectified code for Arduino Nano:

  1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

  int pinLed[] = {10,11,12,13}; int numLed = 4; void setup(){ // Set the mode of each pin to OUTPUT for(int i=0; i<=numLed; i++){ pinMode(pinLed[i], OUTPUT); } } void loop(){ // From pin-2 to pin-5 for(int i=0; i<=numLed; i++){ digitalWrite(pinLed[i], HIGH); delay(500); digitalWrite(pinLed[i], LOW); } // From pin-5 to pin-2 for(int i=numLed-1; i>=0; i--){ digitalWrite(pinLed[i], HIGH); delay(500); digitalWrite(pinLed[i], LOW); } }

2. Mount components onto breadboard, and upload the firmware to board.

   Circuit	Demostration
   	https://i.ibb.co/PCqxrB6/Ardu-Test-Blink-Nano-Breadboard-2024-10-29-115901.gif

3. Practice:

   Use two pins: #2 and #3 to light two LEDs alternatively. Each LED is on for 0.5 seconds and off for 0.5 seconds.

   Code:

   1. Use for to configure each pin

   1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

   int pinLed[] = {2,3}; int numLeds = 2; void setup() { for(int i=0; i<numLeds; i++){ pinMode(pinLed[i], OUTPUT); } } void loop() { for(int i=0; i<numLeds; i++){ digitalWrite(pinLed[i], HIGH); delay(500); digitalWrite(pinLed[i], LOW); delay(500); } }

   Simulation platform: funcode.cc

   

Piezo

Simulation

References:

1. Detect a Knock - Arduino Docs
   • Found in Home / Programming / Built-in Examples - Arduino
2. Piezo sensor with Arduino UNO - How does work Piezo sensor (Code and Circuit Diagram) - YouTube - uSriTu Hobby
   • Searched by Piezo electric disc experiments with Arduino in DDG video
3. Arduino Workshop-Piezo Knock Sensor - Hackster.io
   • Found in s2

Materials:

(2024-10-25)

1. Simulation platform:

SPI LED Array

References:

1. MajicDesigns/MD_Parola
   • Was looking for examples directly using the generic library <SPI.h> instead of calling sensor-specific library. Although Wokwi supports some devices, most of them uses derived libraries.
   • I found wokwi-max7219-matrix Dot Matrix Reference - Wokwi Docs when browsing the Docs of Supported Hardware -> Diagram Reference.
   • One of its ‘Simulator examples’ is Dot Matrix Clock, which writes #include <SPI.h> explicitly.

Notes:

(2024-10-31)

1. A library controlling LED array using SPI interface.

Serial

References:

1. Arduino基础课程07——串行通信 - bilibili - funcodecc
2. Universal Asynchronous Receiver-Transmitter (UART) | Arduino Documentation
   • Searched by Arduino sends and receives character via UART in DDG
3. serial - ‘Serial1’ was not declared in this scope - Arduino Stack Exchange
   • Searched by Arduino Serial exit status 1 Compilation error: 'Serial1' was not declared in this scope in DDG
4. ‘Serial1’ was not declared in this scope - Arduino Forum
   • Found in s3
5. Adding More Serial Ports to your board. - Arduino Docs
   • Refered by r3-SE
6. Arduino项目实战_第四课_串口通信_(3)软串口与双机通信_哔哩哔哩_bilibili - 电子疯狂创客
   • Searched by Arduino nano 串口实验 site:bilibili.com in DDG

Notes:

1. Just connect the Nano board with laptop with a USB cable, then upload the code (r1-Bili):

   1 2 3 4 5 6 7 8

   void setup() { Serial.begin(9600); } void loop() { Serial.println("Hello"); delay(1000); }

(2024-11-29)

2. Serial1 doesn’t exist on Nano or Uno. Nano only has one serial port, called Serial.

   • I think this Serial is not only connected to pins: TX1 and RX0, but also the USB port.

   • Nano has NO pins for Serial1 ^{r4-Forum,r2-Docs}

     However, it can be instantiated with the SoftwareSerial library ^{r3-SE to extend the RX and TX to simulate another serial port on other pins r5-Tutorial:}

     1 2 3 4 5 6 7 8

     #include <SoftwareSerial.h> SoftwareSerial Serial1(3,2); //Rx to pin D3, Tx to pin D2 void setup() { Serial.begin(9600); // Initialize the Serial monitor for debugging Serial1.begin(9600); // Initialize Serial1 for sending data }

(2024-12-05)

3. The SoftwareSerial is an individual serial port, which can do the complete serial function by iteself.

   • Reasons:

     1. Do not mix up the pins of the generic serial (TX1 & RX0). The following image shows two boards are connected with their SoftwareSerial ^r6-bili:

        

     2. Serial.print() will send (wirite) data to the bus.

   • Actions:

     1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32

     #include <SoftwareSerial.h> SoftwareSerial Sserial1(3,2); // RX, TX String str; char c; void setup() { Sserial1.begin(9600); Serial.begin(9600); } void loop() { /* Check the buffer of the SoftwareSerial */ while (Sserial1.available()) { c = Sserial1.read(); /* read 1 byte */ str +=c; if (c == '\n') { /* Use original serial to sent to PC */ Serial.print(str); str = ""; /* Reset str */ } } /* Use the SoftwareSerial to transmit str */ while (Serial.available()) { c = Serial.read(); // Recv str from PC str += c; if (c == '\n') { // Ended with newline /* Use SoftwareSerial to sent to other dev */ Sserial1.print(str); str = ""; } } }

   • Results:

     1. The code in Arduino Docs is equivalent besides the additional SoftwareSerial usage.

Pinout

References:

1. PIN number to use with arduino nano - Arduino Forum
   • Searched by arduino nano pin numbers in DDG
2. • Searched by in

Notes:

1. A pin should be referred to in the program by the number in its name.

   • Although the D1 and A1 have the same “number” 1, but they are gotten controlled with two totally different functions: digitalWrite() and analogWrite().

     The name D13 means the digital pin-13. The combination of a number plus a function digitalWrite/analogWrite is unique; there is no confusion.

     1 2 3

     int pinLed = 13; pinMode(pinLed, OUTPUT); digitalWrite(pinLed, LOW);

     • Do not get confused by other images labeling “pin number”, which are only for breadboard (r1-Forum), such as this image for “Nano Every”.

     For the SS pin, I should look up for D10 pin on the board and use digitalWrite() to control it:

     1 2 3

     int ssPin = 10; pinMode(ssPin, OUTPUT); digitalWrite(ssPin, LOW);