# arduino

* [IDE](#ide)
* [Pinout](#pinout)
* [ESP32](#esp32)
* [Uno](#uno)
  * [Q](#q)
  * [R3](#r3)
* [OLED](#oled)
  * [IDE](#ide-1)
* [3D Case](#3d-case)

## IDE

* \~/.arduinoIDE/arduino-cli.yaml (Linux/macOS)
* C:\Users\YourUsername.arduinoIDE\arduino-cli.yaml (Windows)

```
cd D:\Program Files\Arduino IDE\resources\app\lib\backend\resources

# fix: Client.Timeout
arduino-cli config set network.connection_timeout 600s

# fix: following symlink ... cannot find the path specified
arduino-cli config set directories.data TARGET_DIR
```

## Pinout

| Feature              | GPIO (General-Purpose I/O)                     | PWM (Pulse Width Modulation) | ADC (Analog-to-Digital Converter) |
| -------------------- | ---------------------------------------------- | ---------------------------- | --------------------------------- |
| **Input/Output**     | Both **Input** and **Output**.                 | **Output** only.             | **Input** only.                   |
| **Arduino Function** | `pinMode()`, `digitalWrite()`, `digitalRead()` | `analogWrite()`              | `analogRead()`                    |
| **Mark**             | D\_                                            | \~D\_                        | A\_                               |

AREF: <http://tronixstuff.com/2013/12/12/arduino-tutorials-chapter-22-aref-pin/>

## ESP32

* All: <https://products.espressif.com/#/product-comparison?names=ESP32-C3,ESP32-S3,ESP32-C6\\&type=SoC>
* S3: <https://docs.arduino.cc/hardware/nano-esp32/>
* C3/C6/S3: <https://wiki.seeedstudio.com/SeeedStudio\\_XIAO\\_Series\\_Introduction/#seeed-studio-xiao-series-comparison-table>

## Uno

<https://www.arduino.cc/en/hardware/#uno-family>

### Q

* Debian-capable
* Qualcomm QRB2210 microprocessor (MPU), quad-core 2.0 GHz CPU
* real-time STM32U585 microcontroller (MCU)
* RAM: 2GB LPDDR4
* Storage: 16 GB eMMC built-in (no SD card required)

### R3

Atmel AVR ATmega328P | 8-bit RISC | 16MIPS throughput at 16MHz

* <https://ww1.microchip.com/downloads/en/DeviceDoc/Atmel-7810-Automotive-Microcontrollers-ATmega328P\\_Datasheet.pdf>

<https://store-usa.arduino.cc/products/arduino-uno-rev3>

* INPUT VOLTAGE (LIMIT) 6-20V limit / 7-12V recommended
* DC CURRENT PER I/O PIN 20 mA

<https://content.arduino.cc/assets/A000066-pinout.png>

* 14 digital input/output pins (of which 6 can be used as PWM outputs)
* 6 analog inputs

## OLED

* I2C: 100Khz - 3.4Mhz, many devices on the same bus
* SPI: 4Mhz and up to 100Mhz

### IDE

* Sketch Menu -> Include Library -> Manage Libraries
  * Search: `BusIO` + `adafruit ssd1306`
* File -> Examples

SSD1306 Oled display: <https://create.arduino.cc/projecthub/Arnov\\_Sharma\\_makes/0-96-inch-oled-getting-started-guide-78163a>

```
// Declaration for an SSD1306 display connected to I2C (SDA, SCL pins)
// The pins for I2C are defined by the Wire-library. 
// On an arduino UNO:       A4(SDA), A5(SCL)
// On an arduino MEGA 2560: 20(SDA), 21(SCL)
// On an arduino LEONARDO:   2(SDA),  3(SCL), ...
```

* File -> Examples ---> ssd1306\_128x32\_spi

```
    // Declaration for SSD1306 display connected using software SPI (default case)
    #define OLED_MOSI   9
    #define OLED_CLK   10
    #define OLED_DC    11
    #define OLED_CS    12
    #define OLED_RESET 13
```

## 3D Case

Pro Mini | Wall | <https://www.thingiverse.com/thing:2457807>


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