atmega328p arduino spi problems tft display free sample

I was given one of these displays, identical to the images in earlier posts. After trying it out with the Adafruit libraries, I discovered that my example used the ST7783 driver chip.

I found a couple of posts where people had fixed similar sounding problems by changing some of the settings made to the SST7783 registers when the TFT library initialises the display.

After some trial and error, the following changes to TFTLCD.cpp (in the st7783 library) solved the problem. Near the bottom of the file, there is a PROGMEM array of register addresses and values.

The display is now near perfect. The only issue is that, since the backlight is at one end of the LCD, that end is always a bit brighter than elsewhere.

This new library is a standalone library that contains the TFT driver as well as the graphics functions and fonts that were in the GFX library. This library has significant performance improvements when used with an UNO (or ATmega328 based Arduino) and MEGA.

Examples are included with the library, including graphics test programs. The example sketch TFT_Rainbow_one shows different ways of using the font support functions. This library now supports the "print" library so the formatting features of the "print" library can be used, for example to print to the TFT in Hexadecimal, for example:

To use the F_AS_T performance option the ILI9341 based display must be connected to an MEGA as follows:MEGA +5V to display pin 1 (VCC) and pin 8 (LED) UNO 0V (GND) to display pin 2 (GND)

TFT_ILI9341 library updated on 1st July 2015 to version 12, this latest version is attached here to step 8:Minor bug when rendering letter "T" in font 4 without background fixed

By these two functions, You can find out the resolution of the display. Just add them to the code and put the outputs in a uint16_t variable. Then read it from the Serial port by Serial.println();. First add Serial.begin(9600); in setup().

Spice up your Arduino project with a beautiful large touchscreen display shield with built in microSD card connection. This TFT display is big (4.3" diagonal) bright (8 white-LED backlight) and colorfu 480x272 pixels with individual pixel control. As a bonus, this display has a optional resistive touch panel attached on screen by default.

The shield is fully assembled, tested and ready to go. No wiring, no soldering! Simply plug it in and load up our library - you"ll have it running in under 10 minutes! Works best with any classic Arduino (UNO/Due/Mega 2560).

This display shield has a controller built into it with RAM buffering, so that almost no work is done by the microcontroller. You can connect more sensors, buttons and LEDs.

Of course, we wouldn"t just leave you with a datasheet and a "good luck!" - we"ve written a full open source graphics library at the bottom of this page that can draw pixels, lines, rectangles, circles and text. We also have a touch screen library that detects x,y and z (pressure) and example code to demonstrate all of it. The code is written for Arduino but can be easily ported to your favorite microcontroller!

If you"ve had a lot of Arduino DUEs go through your hands (or if you are just unlucky), chances are you’ve come across at least one that does not start-up properly.The symptom is simple: you power up the Arduino but it doesn’t appear to “boot”. Your code simply doesn"t start running.You might have noticed that resetting the board (by pressing the reset button) causes the board to start-up normally.The fix is simple,here is the solution.

The purpose of this guide is to get your 0.96″ color LCD display successfully operating with your Arduino, so you can move forward and experiment and explore further types of operation with the display. This includes installing the Arduino library, making a succesful board connection and running a demonstration sketch.

Although you can use the display with an Arduino Uno or other boad with an ATmega328-series microcontroller – this isn’t recommended for especially large projects. The library eats up a fair amount of flash memory – around 60% in most cases.

So if you’re running larger projects we recommend using an Arduino Mega or Due-compatible board due to the increased amount of flash memory in their host microcontrollers.

(As the display uses the ST7735S controller IC, you may be tempted to use the default TFT library included with the Arduino IDE – however it isn’t that reliable. Instead, please follow the instructions below).

Please check that the library has been installed – to do this, select the Sketch > Include Libraryoption in the IDE and scroll down the long menu until you see “ER-TFTM0.96-1” as shown below:

The display uses the SPI data bus for communication, and is a 3.3V board. You can use it with an Arduino or other 5V board as the logic is tolerant of higher voltages.

The library used is based on the uTFT library by Henning Karlsen. You can find all the drawing and other commands in the user manual – so download the pdf and enjoy creating interesting displays.

In this article, you will learn how to use TFT LCDs by Arduino boards. From basic commands to professional designs and technics are all explained here.

In electronic’s projects, creating an interface between user and system is very important. This interface could be created by displaying useful data, a menu, and ease of access. A beautiful design is also very important.

There are several components to achieve this. LEDs,  7-segments, Character and Graphic displays, and full-color TFT LCDs. The right component for your projects depends on the amount of data to be displayed, type of user interaction, and processor capacity.

TFT LCD is a variant of a liquid-crystal display (LCD) that uses thin-film-transistor (TFT) technology to improve image qualities such as addressability and contrast. A TFT LCD is an active matrix LCD, in contrast to passive matrix LCDs or simple, direct-driven LCDs with a few segments.

In Arduino-based projects, the processor frequency is low. So it is not possible to display complex, high definition images and high-speed motions. Therefore, full-color TFT LCDs can only be used to display simple data and commands.

In this article, we have used libraries and advanced technics to display data, charts, menu, etc. with a professional design. This can move your project presentation to a higher level.

In electronic’s projects, creating an interface between user and system is very important. This interface could be created by displaying useful data, a menu, and ease of access. A beautiful design is also very important.

There are several components to achieve this. LEDs,  7-segments, Character and Graphic displays, and full-color TFT LCDs. The right component for your projects depends on the amount of data to be displayed, type of user interaction, and processor capacity.

TFT LCD is a variant of a liquid-crystal display (LCD) that uses thin-film-transistor (TFT) technology to improve image qualities such as addressability and contrast. A TFT LCD is an active matrix LCD, in contrast to passive matrix LCDs or simple, direct-driven LCDs with a few segments.

In Arduino-based projects, the processor frequency is low. So it is not possible to display complex, high definition images and high-speed motions. Therefore, full-color TFT LCDs can only be used to display simple data and commands.

In this article, we have used libraries and advanced technics to display data, charts, menu, etc. with a professional design. This can move your project presentation to a higher level.

Size of displays affects your project parameters. Bigger Display is not always better. if you want to display high-resolution images and signs, you should choose a big size display with higher resolution. But it decreases the speed of your processing, needs more space and also needs more current to run.

After choosing the right display, It’s time to choose the right controller. If you want to display characters, tests, numbers and static images and the speed of display is not important, the Atmega328 Arduino boards (such as Arduino UNO) are a proper choice. If the size of your code is big, The UNO board may not be enough. You can use Arduino Mega2560 instead. And if you want to show high resolution images and motions with high speed, you should use the ARM core Arduino boards such as Arduino DUE.

In electronics/computer hardware a display driver is usually a semiconductor integrated circuit (but may alternatively comprise a state machine made of discrete logic and other components) which provides an interface function between a microprocessor, microcontroller, ASIC or general-purpose peripheral interface and a particular type of display device, e.g. LCD, LED, OLED, ePaper, CRT, Vacuum fluorescent or Nixie.

The display driver will typically accept commands and data using an industry-standard general-purpose serial or parallel interface, such as TTL, CMOS, RS232, SPI, I2C, etc. and generate signals with suitable voltage, current, timing and demultiplexing to make the display show the desired text or image.

The LCDs manufacturers use different drivers in their products. Some of them are more popular and some of them are very unknown. To run your display easily, you should use Arduino LCDs libraries and add them to your code. Otherwise running the display may be very difficult. There are many free libraries you can find on the internet but the important point about the libraries is their compatibility with the LCD’s driver. The driver of your LCD must be known by your library. In this article, we use the Adafruit GFX library and MCUFRIEND KBV library and example codes. You can download them from the following links.

You must add the library and then upload the code. If it is the first time you run an Arduino board, don’t worry. Just follow these steps:Go to www.arduino.cc/en/Main/Software and download the software of your OS. Install the IDE software as instructed.

By these two functions, You can find out the resolution of the display. Just add them to the code and put the outputs in a uint16_t variable. Then read it from the Serial port by Serial.println(); . First add Serial.begin(9600); in setup().

First you should convert your image to hex code. Download the software from the following link. if you don’t want to change the settings of the software, you must invert the color of the image and make the image horizontally mirrored and rotate it 90 degrees counterclockwise. Now add it to the software and convert it. Open the exported file and copy the hex code to Arduino IDE. x and y are locations of the image. sx and sy are sizes of image. you can change the color of the image in the last input.

Upload your image and download the converted file that the UTFT libraries can process. Now copy the hex code to Arduino IDE. x and y are locations of the image. sx and sy are size of the image.

In this template, We converted a .jpg image to .c file and added to the code, wrote a string and used the fade code to display. Then we used scroll code to move the screen left. Download the .h file and add it to the folder of the Arduino sketch.

In this template, We used sin(); and cos(); functions to draw Arcs with our desired thickness and displayed number by text printing function. Then we converted an image to hex code and added them to the code and displayed the image by bitmap function. Then we used draw lines function to change the style of the image. Download the .h file and add it to the folder of the Arduino sketch.

In this template, We created a function which accepts numbers as input and displays them as a pie chart. We just use draw arc and filled circle functions.

In this template, We added a converted image to code and then used two black and white arcs to create the pointer of volumes.  Download the .h file and add it to the folder of the Arduino sketch.

In this template, We added a converted image and use the arc and print function to create this gauge.  Download the .h file and add it to folder of the Arduino sketch.

while (a < b) { Serial.println(a); j = 80 * (sin(PI * a / 2000)); i = 80 * (cos(PI * a / 2000)); j2 = 50 * (sin(PI * a / 2000)); i2 = 50 * (cos(PI * a / 2000)); tft.drawLine(i2 + 235, j2 + 169, i + 235, j + 169, tft.color565(0, 255, 255)); tft.fillRect(200, 153, 75, 33, 0x0000); tft.setTextSize(3); tft.setTextColor(0xffff); if ((a/20)>99)

while (b < a) { j = 80 * (sin(PI * a / 2000)); i = 80 * (cos(PI * a / 2000)); j2 = 50 * (sin(PI * a / 2000)); i2 = 50 * (cos(PI * a / 2000)); tft.drawLine(i2 + 235, j2 + 169, i + 235, j + 169, tft.color565(0, 0, 0)); tft.fillRect(200, 153, 75, 33, 0x0000); tft.setTextSize(3); tft.setTextColor(0xffff); if ((a/20)>99)

In this template, We display simple images one after each other very fast by bitmap function. So you can make your animation by this trick.  Download the .h file and add it to folder of the Arduino sketch.

In this template, We just display some images by RGBbitmap and bitmap functions. Just make a code for touchscreen and use this template.  Download the .h file and add it to folder of the Arduino sketch.

This is a graphics library for the family of small colour TFT displays based on the ST7735 and ST7789 driver chips. These are really nice displays; bright, colourful, available in a variety of useful sizes, and available at low cost from suppliers like Adafruit, AliExpress, or Banggood:

This library allows you to plot points, draw lines, draw filled rectangles, and plot text with an optional scale factor. I"ve included a demo histogram-plotting program that adjusts itself to fit each of the displays I"ve supported.

Unlike most other TFT display libraries this one doesn"t require a memory buffer, allowing it to be run on any processor down to an ATtiny85. The displays are SPI and require four pins to drive the display, leaving one pin free on an ATtiny85 to interface to another device, such as a temperature sensor. If you need more pins choose a larger chip, such as the ATtiny84; see Using the library with other AVR chips at the end of the article for information about how to convert the code for different chips.

I"ve published a library for a colour OLED display in a previous article: Colour Graphics Library. The main difference between the colour TFT displays and the colour OLED displays is that the TFT displays are not self-illuminating, and so need a backlight; they therefore have a slightly higher power consumption. However, they are exceedingly cheap, and they are available in larger sizes than the colour OLED displays.

This library will work with displays based on the ST7735 which supports a maximum display size of 132 (H) x 162 (V), or the similar ST7789 which supports a maximum display size of 240 (H) x 320 (V).

The display driver interfaces to the displays with the longer side as the vertical dimension, which is why the rectangular displays are usually listed with the longer dimension second. My library allows you to rotate the image for any desired orientation.

All the Adafruit breakout boards for these displays include level-shifting circuitry, so they will work with either 5V or 3.3V microcontroller boards. They also include an SD card socket, if that"s of interest to you. The Adafruit boards have pullups on the backlight and reset pins, so the display will work if you leave these pins unconnected.

The pullup resistor from the display"s CS pin is optional; it holds the chip select high to prevent the display from being affected by the ISP signals while programming the ATtiny85.

The different displays are catered for by six constants which specify the size of the display, the offsets relative to the area supported by the display driver, whether the display is inverted, and the rotation value; for example:

Note that on some displays you may also have to change the xoff or yoff value when rotating the display. For example, to rotate the image on the 240x240 displays by 180° use the settings:

To check or adjust the values for each display I ran this program, which draws a one-pixel border around the display area, and plots an "F" to show the orientation:

The ATtiny85 and other AVR processors supports toggling of one or more bits in a port, so provided you set all the pins to their disabled state at startup, for speed the display access routines can simply toggle the appropriate pins to enable or disable them.

The InitDisplay() routine first defines the four display pins as outputs, and takes the SCK, DC, and CS pins high (inactive). It then sends the essential configuration commands to the display.

The display memory stores 18 bits per pixel: 6 bits per colour. However, you can write to the display in three alternative modes, with 12, 16, or 18 bits per pixel. I chose the 16 bit mode, which assigns 5 bits to red, 6 bits to green, and 5 bits blue. It"s the most convenient one to work with as you simply send two bytes to define the colour of each pixel.

To clear the display the ClearDisplay() routine sends the appropriate number of zero bytes. The routine temporarily switches to 12-bit colour mode, which reduces the time to clear the display by 25%:

The library includes basic graphics routines for plotting points and drawing lines. These work on a conventional coordinate system with the origin at lower left. For example, on the 80x160 display:

My first version of PlotChar() plotted characters by calling PlotPoint() for each pixel. However, I then tried the following alternative approach which defines an area of the display using the CASET (Column Address Set) and RASET (Row Address Set) commands, and then sends a stream of the appropriate bytes to define the character. This turned out to be over three times faster!

14th January 2020: Tested the program with the Adafruit 1.3" 240x240 TFT display, and updated the program to correct a problem when rotating the image on that display.

ok, glad I asked. Most SPI devices need to have a CS (Chip Select) or CSN (Chip Select Not -- same behavior, different label) so that the MCU (the nano) can tell which SPI device to pay attention to the communication happening on the SPI bus (MISO, MOSI, & SCK/SCLK pins). Without attaching the ST7789"s CS pin to the MCU, the display is likely paying attention to all communication over the SPI bus, even when the data over MOSI is only intended for the nRF24.

According to the code you posted, and the adafruit library for the ST7789, you are trying to use software driven SPI data over the nano"s designated pins for hardware driven SPI. I highly recommend you change the TFT_MOSI & TFT_SCLK pins to something that isn"t also attached the nRF24. Or just use the ST7789"s CS pin. Notice that the ST7789 is one of those few SPI devices that doesn"t use the MISO (because its an output only device).

p.s. SCL & SDA are terms usually reserved for the I2C bus, but they are often used as a reference for the SPI pins SCK & MOSI/MISO (as evident by the ST7789 datasheet which doesn"t explicitly mention using I2C). I"ve also seen SDO & DO used for MOSI and SDI & DI used for MISO. The SCK/SCLK pin shares the same identical role as the SCL (again just different labels for a different interfacing bus).

This library enables you to use Hardware-based PWM channels on Arduino AVR ATtiny-based boards (ATtiny3217, etc.), using megaTinyCore, to create and output PWM to pins.

This library enables you to use ISR-based PWM channels on Arduino AVR ATtiny-based boards (ATtiny3217, etc.), using megaTinyCore, to create and output PWM any GPIO pin.

Small low-level classes and functions for Arduino: incrementMod(), decToBcd(). strcmp_PP(), PrintStr, PrintStrN, printPad{N}To(), printIntAsFloat(), TimingStats, formUrlEncode(), FCString, KString, hashDjb2(), binarySearch(), linearSearch(), isSorted(), reverse(), and so on.

Cyclic Redundancy Check (CRC) algorithms (crc8, crc16ccitt, crc32) programmatically converted from C99 code generated by pycrc (https://pycrc.org) to Arduino C++ using namespaces and PROGMEM flash memory.

Various sorting algorithms for Arduino, including Bubble Sort, Insertion Sort, Selection Sort, Shell Sort (3 versions), Comb Sort (4 versions), Quick Sort (3 versions).

Date, time, timezone classes for Arduino supporting the full IANA TZ Database to convert epoch seconds to date and time components in different time zones.

Clock classes for Arduino that provides an auto-incrementing count of seconds since a known epoch which can be synchronized from external sources such as an NTP server, a DS3231 RTC chip, or an STM32 RTC chip.

Useful Arduino utilities which are too small as separate libraries, but complex enough to be shared among multiple projects, and often have external dependencies to other libraries.

Fast and compact software I2C implementations (SimpleWireInterface, SimpleWireFastInterface) on Arduino platforms. Also provides adapter classes to allow the use of third party I2C libraries using the same API.

Enables Bluetooth® Low Energy connectivity on the Arduino MKR WiFi 1010, Arduino UNO WiFi Rev.2, Arduino Nano 33 IoT, Arduino Nano 33 BLE and Nicla Sense ME.

Fully Asynchronous UDP Library for RASPBERRY_PI_PICO_W using CYW43439 WiFi with arduino-pico core. The library is easy to use and includes support for Unicast, Broadcast and Multicast environments.

The last hope for the desperate AVR programmer. A small (344 bytes) Arduino library to have real program traces and to find the place where your program hangs.

Enable inclusion of both ESP32 Blynk BT/BLE and WiFi libraries. Then select one at reboot or run both. Eliminate hardcoding your Wifi and Blynk credentials and configuration data saved in either LittleFS, SPIFFS or EEPROM.

Simple Ethernet Manager for MultiBlynk for Teensy, SAM DUE, SAMD21, SAMD51, nRF52, ESP32, ESP8266, RP2040-based (Nano_RP2040_Connect, RASPBERRY_PI_PICO) boards, etc. with or without SSL, configuration data saved in ESP8266/ESP32 LittleFS, SPIFFS, nRF52/RP2040 LittleFS/InternalFS, EEPROM, DueFlashStorage or SAMD FlashStorage.

Simple GSM shield Credentials Manager for Blynk and ESP32 / ESP8266 boards, with or without SSL, configuration data saved in LittleFS / SPIFFS / EEPROM.

Simple WiFiManager for Blynk and ESP32 with or without SSL, configuration data saved in either SPIFFS or EEPROM. Enable inclusion of both ESP32 Blynk BT/BLE and WiFi libraries. Then select one at reboot or run both. Eliminate hardcoding your Wifi and Blynk credentials and configuration data saved in either LittleFS, SPIFFS or EEPROM. Using AsyncWebServer instead of WebServer, with WiFi networks scanning for selection in Configuration Portal.

Simple GSM shield Credentials Manager for Blynk and ESP32 / ESP8266 boards, with or without SSL, configuration data saved in LittleFS / SPIFFS / EEPROM.

Simple Async WiFiManager for Blynk and ESP32 (including ESP32-S2, ESP32-C3), ESP8266 with or without SSL, configuration data saved in either LittleFS, SPIFFS or EEPROM. Now working with new ESP8266 core v3.0.1 and ESP32 core v1.0.6

Simple WiFiManager for Blynk and ESP32 (including ESP32-S2, ESP32-C3), ESP8266 with or without SSL, configuration data saved in either LittleFS, SPIFFS or EEPROM. Now working with new ESP8266 core v3.0.0 and ESP32 core v1.0.6

An Arduino library that takes input in degrees and output a string or integer for the 4, 8, 16, or 32 compass headings (like North, South, East, and West).

DSpotterSDK_Maker_33BLE provides offline speech recognition function for developers on Arduino Nano 33 BLE Sense, which can recognize trigger words and command words.

DSpotterSDK_Maker_PortentaH7 provides offline speech recognition function for developers on Arduino Portenta H7, which can recognize trigger words and command words.

DSpotterSDK_Maker_RP2040 provides offline speech recognition function for developers on Arduino Nano RP2040 Connect, which can recognize trigger words and command words.

Directly interface Arduino, esp8266, and esp32 to DSC PowerSeries and Classic security systems for integration with home automation, remote control apps, notifications on alarm events, and emulating DSC panels to connect DSC keypads.

This library enables you to use Hardware-based PWM channels on Arduino AVRDx-based boards (AVR128Dx, AVR64Dx, AVR32Dx, etc.), using DxCore, to create and output PWM.

This library enables you to use ISR-based PWM channels on Arduino AVRDx-based boards (AVR128Dx, AVR64Dx, AVR32Dx, etc.), using DxCore, to create and output PWM any GPIO pin.

Small and easy to use Arduino library for using push buttons at INT0/pin2 and / or any PinChangeInterrupt pin.Functions for long and double press detection are included.Just connect buttons between ground and any pin of your Arduino - that"s itNo call of begin() or polling function like update() required. No blocking debouncing delay.

Arduino library for controlling standard LEDs in an easy way. EasyLed provides simple logical methods like led.on(), led.toggle(), led.flash(), led.isOff() and more.

OpenTherm Library to control Central Heating (CH), HVAC (Heating, Ventilation, Air Conditioning) or Solar systems by creating a thermostat using Arduino IDE and ESP32 / ESP8266 hardware.

WizFi360/ESP8266/ESP32-AT library for Arduino providing an easy-to-use way to control WizFi360/ESP8266-AT/ESP32-AT WiFi shields using AT-commands. For AVR, Teensy, SAM DUE, SAMD21, SAMD51, STM32, nRF52, SIPEED_MAIX_DUINO and RP2040-based (Nano_RP2040_Connect, RASPBERRY_PI_PICO, etc.) boards using WizFi360/ESP8266/ESP32 AT-command shields.

Library to detect a multi reset within a predetermined time, using RTC Memory, EEPROM, LittleFS or SPIFFS for ESP8266 and ESP32, ESP32_C3, ESP32_S2, ESP32_S3

Simple Ethernet Manager for Teensy, SAM DUE, SAMD, nRF52, ESP32 (including ESP32-S2/C3), ESP8266, RP2040-based Nano_RP2040_Connect, RASPBERRY_PI_PICO, etc. boards. Config data saved in ESP LittleFS, SPIFFS or EEPROM, nRF52 LittleFS, EEPROM, DueFlashStorage or SAMD FlashStorage.

ezTime - pronounced "Easy Time" - is a very easy to use Arduino time and date library that provides NTP network time lookups, extensive timezone support, formatted time and date strings, user events, millisecond precision and more.

A library for implementing fixed-point in-place Fast Fourier Transform on Arduino. It sacrifices precision and instead it is way faster than floating-point implementations.

The GCodeParser library is a lightweight G-Code parser for the Arduino using only a single character buffer to first collect a line of code (also called a "block") from a serial or file input and then parse that line into a code block and comments.

Arduino library for the Flysky/Turnigy RC iBUS protocol - servo (receive) and sensors/telemetry (send) using hardware UART (AVR, ESP32 and STM32 architectures)

An Arduino library to control the Iowa Scaled Engineering I2C-IRSENSE ( https://www.iascaled.com/store/I2C-IRSENSE ) reflective infrared proximity sensor.

Convinient way to map a push-button to a keyboard key. This library utilize the ability of 32u4-based Arduino-compatible boards to emulate USB-keyboard.

This library allows you to easily create light animations from an Arduino board or an ATtiny microcontroller (traffic lights, chaser, shopkeeper sign, etc.)

LiquidCrystal fork for displays based on HD44780. Uses the IOAbstraction library to work with i2c, PCF8574, MCP23017, Shift registers, Arduino pins and ports interchangably.

This library enables you to use ISR-based PWM channels on RP2040-based boards, such as Nano_RP2040_Connect, RASPBERRY_PI_PICO, with Arduino-mbed (mbed_nano or mbed_rp2040) core to create and output PWM any GPIO pin.

Arduino library for MCP4728 quad channel, 12-bit voltage output Digital-to-Analog Convertor with non-volatile memory and I2C compatible Serial Interface

This library enables you to use ISR-based PWM channels on an Arduino megaAVR board, such as UNO WiFi Rev2, AVR_Nano_Every, etc., to create and output PWM any GPIO pin.

Replace Arduino methods with mocked versions and let you develop code without the hardware. Run parallel hardware and system development for greater efficiency.

A library package for ARDUINO acting as ModBus slave communicating through UART-to-RS485 converter. Originally written by Geabong github user. Improved by Łukasz Ślusarczyk.

This library enables you to use ISR-based PWM channels on an nRF52-based board using Arduino-mbed mbed_nano core such as Nano-33-BLE to create and output PWM any GPIO pin.

This library enables you to use ISR-based PWM channels on an nRF52-based board using Adafruit_nRF52_Arduino core such as Itsy-Bitsy nRF52840 to create and output PWM any GPIO pin.

An Arduino library for the Nano 33 BLE Sense that leverages Mbed OS to automatically place sensor measurements in a ring buffer that can be integrated into programs in a simple manner.

his library enables you to use Hardware-based PWM channels on RP2040-based boards, such as Nano_RP2040_Connect, RASPBERRY_PI_PICO, with either Arduino-mbed (mbed_nano or mbed_rp2040) or arduino-pico core to create and output PWM to any GPIO pin.

This library enables you to use SPI SD cards with RP2040-based boards such as Nano_RP2040_Connect, RASPBERRY_PI_PICO using either RP2040 Arduino-mbed or arduino-pico core.

This library enables you to use ISR-based PWM channels on RP2040-based boards, such as ADAFRUIT_FEATHER_RP2040, RASPBERRY_PI_PICO, etc., with arduino-pico core to create and output PWM any GPIO pin.

The most powerful and popular available library for using 7/14/16 segment display, supporting daisy chaining so you can control mass amounts from your Arduino!

Provides methods to retrieve instant and peak values from the ADC input. The Arduino library SensorWLED splits the input from a varying analog signal from the ADC into components, i.e., provides the capability of a sample-and-hold circuit.

Enables smooth servo movement. Linear as well as other (Cubic, Circular, Bounce, etc.) ease movements for servos are provided. The Arduino Servo library or PCA9685 servo expanders are supported.

Use the low-power high-resolution ICM 20948 9 DoF IMU from Invensense with I2C or SPI. Version 1.2 of the library includes support for the InvenSense Digital Motion Processor (DMP™).

Enables reading and writing on SD card using SD card slot connected to the SDIO/SDMMC-hardware of the STM32 MCU. For slots connected to SPI-hardware use the standard Arduino SD library.

Menu library for Arduino with IoT capabilities that supports many input and display devices with a designer UI, code generator, CLI, and strong remote control capability.

Adds tcUnicode UTF-8 support to Adafruit_GFX, U8G2, tcMenu, and TFT_eSPI graphics libraries with a graphical font creation utility available. Works with existing libraries

A library for creating Tickers which can call repeating functions. Replaces delay() with non-blocking functions. Recommanded for ESP and Arduino boards with mbed behind.

This library enables you to use Interrupt from Hardware Timers on an Arduino, Adafruit or Sparkfun AVR board, such as Nano, UNO, Mega, Leonardo, YUN, Teensy, Feather_32u4, Feather_328P, Pro Micro, etc.

This library enables you to use Interrupt from Hardware Timers on supported Arduino boards such as AVR, Mega-AVR, ESP8266, ESP32, SAMD, SAM DUE, nRF52, STM32F/L/H/G/WB/MP1, Teensy, Nano-33-BLE, RP2040-based boards, etc.

A simple library to display numbers, text and animation on 4 and 6 digit 7-segment TM1637 based display modules. Offers non-blocking animations and scrolling!

Really tiny library to basic RTC functionality on Arduino. DS1307, DS3231 and DS3232 RTCs are supported. See https://github.com/Naguissa/uEEPROMLib for EEPROM support. Temperature, Alarms, SQWG, Power lost and RAM support.

Monochrome LCD, OLED and eInk Library. Display controller: SSD1305, SSD1306, SSD1309, SSD1312, SSD1316, SSD1318, SSD1320, SSD1322, SSD1325, SSD1327, SSD1329, SSD1606, SSD1607, SH1106, SH1107, SH1108, SH1122, T6963, RA8835, LC7981, PCD8544, PCF8812, HX1230, UC1601, UC1604, UC1608, UC1610, UC1611, UC1617, UC1638, UC1701, ST7511, ST7528, ST7565, ST7567, ST7571, ST7586, ST7588, ST75160, ST75256, ST75320, NT7534, ST7920, IST3020, IST3088, IST7920, LD7032, KS0108, KS0713, HD44102, T7932, SED1520, SBN1661, IL3820, MAX7219, GP1287, GP1247, GU800. Interfaces: I2C, SPI, Parallel.

True color TFT and OLED library, Up to 18 Bit color depth. Supported display controller: ST7735, ILI9163, ILI9325, ILI9341, ILI9486,LD50T6160, PCF8833, SEPS225, SSD1331, SSD1351, HX8352C.

RFC6455-based WebSockets Server and Client for Arduino boards, such as nRF52, Portenta_H7, SAMD21, SAMD51, STM32F/L/H/G/WB/MP1, Teensy, SAM DUE, RP2040-based boards, besides ESP8266/ESP32 (ESP32, ESP32_S2, ESP32_S3 and ESP32_C3) and WT32_ETH01. Ethernet shields W5100, W5200, W5500, ENC28J60, Teensy 4.1 NativeEthernet/QNEthernet or Portenta_H7 WiFi/Ethernet. Supporting websocket only mode for Socket.IO. Ethernet_Generic library is used as default for W5x00. Now supporting RP2040W

Enables network connection (local and Internet) and WiFiStorage for SAM DUE, SAMD21, SAMD51, Teensy, AVR (328P, 32u4, 16u4, etc.), Mega, STM32F/L/H/G/WB/MP1, nRF52, NINA_B302_ublox, NINA_B112_ublox, RP2040-based boards, etc. in addition to Arduino MKR WiFi 1010, Arduino MKR VIDOR 4000, Arduino UNO WiFi Rev.2, Nano 33 IoT, Nano RP2040 Connect. Now with fix of severe limitation to permit sending much larger data than total 4K and using new WiFi101_Generic library

Universal Timer with 1 millisecond resolution, based on system uptime (i.e. Arduino: millis() function or STM32: HAL_GetTick() function), supporting OOP principles.

The Arduino Uno is probably the most popular Arduino board, and for good reason.  It’s relatively small, very inexpensive (especially clone boards) and has a wealth of support code and documentation. It’s also likely the first Arduino board you started working with, for some of you it may even be the only Arduino board you own.

You’ll find that the majority of projects and demonstrations that I perform on this website and on the YouTube channel use an Arduino Uno. It’s also my favorite Arduino board.

But the real value of the Arduino Uno is as a development or prototyping board.  With an Arduino Uno and a solderless breadboard you can quickly bring ideas and concepts to life, its connectors work well with jumper wires and the wealth of code available for the Arduino platform makes development tasks a breeze.

After you finish you’ll have a working project but it may not be a practical one to use in the real world. It has no enclosure and as it consists of an Arduino Uno, a solderless breadboard and various wires, modules, and components. It’s actually pretty fragile.

One big thing that you’ll need to factor into your decision is the Arduino Uno itself. It may be perfect for your permanent project, but again, it may not be.

The Arduino Uno is a wonderful device. With a generous helping of digital I/O ports, 8 analog-to-digital converters, I2C, Serial and SPI interfaces and onboard voltage regulation it is suitable for powering a wide variety of devices. It has a built-in USB port and onboard LEDs and can provide both 5-volt and 3.3-volt low-current power supplies for your peripheral devices.

The Arduino Nano– This small board can do everything an Arduino Uno can, it even has two additional analog to digital converters. It has a mini USB connector instead of the bulky Type B connector used on the Arduino Uno. Cost wise it’s a bit less expensive.

The ATmega328– This is the solution you’ll be reading about in this article.  It’s the microcontroller that powers the Arduino Uno, and it can be used all on its own.

The original Arduino Uno and its clones used the 28-pin DIP (Dual Inline Package) version of the ATmega328. Other clones and boards like the Nano and Pro Mini make use of surface mount versions, this explains why the Nano and Pro Mini have two additional analog to digital converters.

As you can see from the diagram above the ATmega328 has several pins that have two, or even three, functions. You can change the functions of these pins programmatically within your sketch, the same is true of the Arduino Uno (which makes perfect sense as the Uno is based upon the ATmega328).

When converting your design from an Arduino Uno to a raw ATmega328 chip it is helpful to be able to relate the pinouts on the ATmega328 to the connections on an Arduino Uno.  The following pinout diagram has been relabeled to show the Arduino Uno equivalent functions:

An example might be helpful to help you equate the pins on an Arduino to those on an ATmega328.  For that reason, I’ve put together a very simple project that can be quickly prototyped on an Arduino Uno. We will then look at what is required to move our simple project to an ATmega328.

After building this you’ll realize that using an entire Arduino Uno is a real overkill, as only three digital I/O pins are put to use. It also would lend itself well to being mounted into a Star Wars toy or a custom 3D-printed enclosure.

I took the easy road and used an excellent sketch that has been on GitHub for over 6 years. It is theArduino Song sketch by Nick Sort, you can take a look at it here:

If you look closely an an Arduino Uno board you’ll notice that aside from the ATmega328 there really are not very many components. Most of the “extra” parts have to do with either the USB to serial interface or with the internal 5-volt and 3.3-volt regulators.

In actual fact, you can put together a functional equivalent of an Arduino Uno using only an ATmega328 and five parts. You can even wire on up without any additional parts if you are willing to run it at a lower clock frequency.

A “bootloader” is code that is burned onto the ATmega328 chips EEPROM. This code is loaded when the processor is powered up or reset and it sets up things like the clock frequency and a number of the internal registers. It also gets the ATmega328 ready to accept programs from the Arduino IDE on its serial RX and TX pins.

The Arduino Bootloader is essentially what makes an ATmega328 into an “Arduino”. It is open source code that is already available in your Arduino IDE, and you can use the Arduino IDE to load a bootloader into a blank ATmega328 chip.

You might not need to do this though. You can purchase an ATmega328 with the bootloader already installed. That is what I did for this project. Look for an ATmega328 chip that has the letters “PU” at the end of the part number, i.e. ATmega328P-PU.

If you do need to burn your own bootloader there are many resources that will show you how, including the one on theofficial Arduino website. You can also get dedicated devices that burn bootloaders automatically, useful if you have dozens or hundreds of chips to set up.

Assuming that you have an ATmega328 with a bootloader burned onto it you are now ready to wire it up. You will need a few extra components for your “homemade Arduino”.

You can use an Arduino Uno to load the sketch onto the ATmega328, but only if you have the right kind of Arduino Uno.  Let me explain what I mean by “right kind”:

The original Arduino Uno, as well as several clones, use a 28-pin DIP version of the ATmega328. The same type of ATmega328 that we are going to be programming.

This chip was mounted in an IC socket and thus can be removed. And the ability to remove the chip from its socket provides us with two methods of using the Arduino Uno to program an ATmega328 for our stand-alone configuration.

Of course, if your Arduino Uno clone uses a surface mount chip then you’re out of luck. But fear not, there is a third method of programming an ATmega328 that doesn’t require an Arduino Uno at all.

Simply use the Arduino Uno as you normally would and program your sketch onto it.  Then carefully remove the ATmega328 from your Arduino Uno and use it on the breadboard, wired as we have seen earlier.

The IC socket on the Arduino Uno is not really made for repeated removals and insertions. Eventually, you will degrade or damage it if you do this a lot.

The second method also requires an Arduino Uno that has a 28-pin DIP version of the ATmega328. As with the first method you’ll need to remove the processor from the Arduino board. Unlike the first method, however, you will just be putting the ATmega328 aside. After we are done you can put it back into the IC socket.

This method will make use of the USB to serial converter that is built into the Arduino Uno. The outputs of this converter are always available on pins 0 and 1 of the Uno’s digital I/O connecter.  With this method we will just send those outputs to our ATmega328 on a breadboard.

Again remember,although it isn’t shown in the diagram above you need to have all of the other wiring to the ATMega328 as well. This diagram only shows theadditional connections you need to make using the Arduino Uno!

What you are doing is tying the RX (receive) pin of the Arduino Uno to the RX pin on the ATmega328 (pin2). You are also connecting the TX (transmit) pin on the Uno to the ATmega328 TX pin (pin 3). And, finally, the Reset pin on the Arduino Uno is connected to the Reset pin on pin 1 of the ATmega328.

There seems to be a lot of conflicting advice on the web regarding how you setup the Arduino IDE to program your ATmega328 using this method. Some suggest that you change the board type.

I have not found that to be necessary. I just leave my Arduino IDE set exactly as it was when programming my Arduino Uno normally. And it worked every time.

When you are loading your sketch you should notice that a few of the LEDs on the Arduino Uno wil blink, just like they do normally. It’s a good indication that everything is working properly.

But what do you do if your Arduino clone uses a surface mount chip, or if you just don’t want to pull the chip out of the socket on your board? Let’s look at another method that doesn’t use an Arduino Uno at all.

The FTDI Adapter is a USB to serial convertor that is commonly used to program an Arduino Pro Mini and other microcontrollers that do not have a USB port. The “FTDI” abbreviation comes from the original manufacturers’ name, a Scottish company calledFuture Technology Devices International.

Also, note that unlike the previous method which used the Arduino Uno the FTDI method requires you to reverse transmit and receive. So the RX output from the FTDI adapter connects to the TX pin (pin 3) on the ATmega328 and the TX output from the FTDI adapter is attached to the RX pin (pin 2) on the ATmega328.

Once again I found I didn’t need to make any changes in my Arduino IDE, it just worked as it always did. One thing to note however is that the computer in my workshop is LINUX (Ubuntu 16.04) and if you are using a Windows computer you may need to install a driver to use the FTDI adapter.

This method of programming an ATmega328 has a lot of advantages once you get it working, the primary one being that it is completely independent and does not require you to modify an Arduino Uno.

Learn how to transfer your Arduino Uno projects to an ATmega328 chip so you can create a permanent version in a custom enclosure. Uses a Star Wars music box as an example.

I am working on a simple AVR C project with an ultrasonic sensor (HC-SR04) and SPI communication between the ATmega328P (Arduino) and three cascaded MAX7219 LCD matrix. The objective of the system is to detect and measure the distance using the ultrasonic sensor and display an appropriate message on the LCD matrix simultaneously.

I can perform the main functionality of both components separately. I can detect and measure distance with the HC-SR04 and I can display the text on the LCD matrix and scroll the text as well. The HC-SR04 repeatedly measures the distance roughly every 5ms.

The problem rises when I want to perform both functionalities simultaneously. What happens is that the text message is displayed repeatedly on the LCD matrix but not in full. I understand this is because I repeatedly measure the distance using the ultrasonic sensor. My guess would be interrupts, however I am not sure how to tackle this issue.