SparkFun Qwiic Alphanumeric Display Hookup Guide

2022-04-14 | By SparkFun Electronics

License: See Original Project

Guide by ELL C, MAKIN-STUFF

Introduction

Seven segment displays are SO 2020. I mean, we see them in our clocks, ovens, and microwaves ‎on the daily. But what happens when you add more segments to each digit? You can upgrade your ‎appliances and let everyone know how you REALLY feel. Introducing SparkFun's newest Qwiic-‎Enabled Alphanumeric Display in Pink, Green, Blue, Red, Purple, and White. Customize that ‎microwave alert - "Your food is done, fool!" Or hack those oven messages - "I pity the fool that ‎doesn't pre-heat!" These fourteen-segment digits allow you display all sorts of numbers, characters, ‎and symbols. Let's jump in and have a look, shall we?‎

Required Materials

You will need a microcontroller to control the Qwiic Alphanumeric Display in order to follow along ‎with this tutorial. Below are a few options that come Qwiic-enabled out of the box:‎

If your chosen microcontroller is not already Qwiic-enabled, you can add that functionality with one ‎or more of the following items:‎

You will also need at least one Qwiic cable to connect your Alphanumeric Display to your ‎microcontroller.‎

Suggested Reading

If you aren't familiar with the Qwiic system, we recommend reading here for an overview:‎

qwiic_1

We would also suggest reading through the following tutorials if you are not familiar with the ‎concepts covered in them:‎

Serial Communication: Asynchronous serial communication concepts: packets, signal levels, ‎baud rates, UARTs and more!‎

I2C: An introduction to I2C, one of the main embedded communications protocols in use today.‎

Hardware Overview

As mentioned in the introduction, the Qwiic Alphanumeric Displays use the VK16K33 LED driver ‎chip to control the segments. In this section of the guide, we'll go into more detail on the LED driver ‎and the display, as well as the other components included on the board.‎

VK16K33 LED Driver

The Qwiic Alphanumeric Display boards use the VK16K33 LED driver chip to control the segments. ‎The VK16K33 is a memory mapping and multifunction LED controller driver with a maximum display ‎segment number of 128 patterns (16 segments and 8 commons) and a 13×3 matrix key scan circuit. ‎There's an integrated RC oscillator and a 16-step dimming circuit as well. More information can be ‎found in the VK16K33 Datasheet.‎

driver_2

Alphanumeric Display

Look at all those beautiful segments ready to display (almost) whatever your heart desires!‎

display_3

Qwiic

Our Qwiic Ecosystem makes sensors pretty much plug and play. There are two Qwiic connectors ‎on either side of the Alphanumeric Display board to provide power and I²C connectivity ‎simultaneously.‎

The default I²C address of the board is 0x70. Additional addresses are available - see ‎the Jumpers section below.‎

address_4

I²C Address Jumpers

Two jumpers have been provided to allow you to choose the I²C address of the peripheral. See the ‎table below for configuration details.‎

jumpers_5

table_6

I²C Bus Resistor Jumper

The Qwiic Alphanumeric Display Breakout has onboard I²C pull up resistors; if multiple sensors are ‎connected to the bus with the pull-up resistors enabled, the parallel equivalent resistance will create ‎too strong of a pull-up for the bus to operate correctly. As a general rule of thumb, disable all but ‎one pair of pull-up resistors if multiple devices are connected to the bus. If you need to disconnect ‎the pull up resistors, they can be removed by cutting the traces on the corresponding jumpers ‎highlighted below.‎

i2c_7

I²C Pins

If you've got mad soldering skills and really want to access the I²C pins, we've made these bad boys ‎available to you.

Check it:‎

C - SCL
D - SDA
‎3 - 3.3V
G - GND

check_8

Board Outline

Each Alphanumeric Display Breakout board measures 1.6" x 1.1".‎

display_9

Hardware Hookup

Using the Qwiic system, assembling the hardware is a breeze. All you need to do is connect your ‎SparkFun Qwiic Alphanumeric Display to your chosen development board with a Qwiic cable ‎or adapter cable.‎

hookup_10

If you decide to use the PTH pins broken out on the display you will need to solder some headers ‎to them. If you are not familiar with through-hole soldering take a look at this tutorial:‎

solder_11

How to Solder: Through-Hole Soldering

This tutorial covers everything you need to know about through-hole soldering.‎

SparkFun Alphanumeric Display Library

With the display connected to your microcontroller it's time to get started using the SparkFun ‎Alphanumeric Display Library!‎

Alphanumeric Display Arduino Library

Note: Make sure you are using the latest stable version of the Arduino IDE on your desktop. If this ‎is your first-time using Arduino IDE, library, or board add-on, please review the following tutorials. ‎

Before we get started, we'll need to download and install SparkFun's Alphanumeric Display Arduino ‎library. You can use the Arduino Library Manager by searching "SparkFun Alphanumeric Display" ‎to automatically install. Or you can download the library and install it using the button below.‎

DOWNLOAD THE SPARKFUN ALPHANUMERIC DISPLAY ARDUINO LIBRARY (ZIP)‎

Before we get started developing a sketch, let's look at the available functions of the library.‎

bool setBrightness(uint8_t duty); --- This sets the brightness for all units
setBrightnessSingle(uint8_t displayNumber, uint8_t duty); --- This sets the brightness ‎for a single unit
setBlinkRate(float rate); --- Set the refresh rate for all units
setBlinkRateSingle(uint8_t displayNumber, float rate); --- Set the refresh rate for a ‎single unit
displayOn(); --- Turn all display units on
displayOff(); --- Turn all display units off
displayOnSingle(uint8_t displayNumber); --- Turn a single display unit on
displayOffSingle(uint8_t displayNumber); --- Turn a single display unit off
setDisplayOnOff(uint8_t displayNumber, bool turnOnDisplay); --- Set or clear the display ‎on/off bit
enableSystemClock(); --- Turn on the system oscillator for all displays on the I2C bus
disableSystemClock(); --- Turn off the system oscillator for all displays on the bus
enableSystemClockSingle(uint8_t displayNumber); --- Turn on the system oscillator for ‎normal operation mode
disableSystemClockSingle(uint8_t displayNumber); --- Turn off the system oscillator for ‎standby mode
illuminateSegment(uint8_t segment, uint8_t digit); --- Given a segment and a digit, set ‎the matching bit within the RAM of the Holtek RAM set
illuminateChar(uint16_t disp, uint8_t digit); --- Given a binary set of segments and a ‎digit, store this data into the RAM array
printChar(uint8_t displayChar, uint8_t digit); --- Print a character, for a given digit, on ‎display
updateDisplay(); --- Push the contents of displayRAM out to the various displays in 16 byte ‎chunks
defineChar(uint8_t displayChar, uint16_t segmentsToTurnOn); --- Update the list to define ‎a new segments display for a particular character
getSegmentsToTurnOn (uint8_t charPos); --- Get the character map from the definition list or ‎default table
decimalOn(); --- Turn the decimal on for all displays on bus
decimalOff(); --- Turn the decimal off for all displays on bus
decimalOnSingle(uint8_t displayNumber); --- Turn the decimal point on for a single display
decimalOffSingle(uint8_t displayNumber); --- Turn the decimal point off for a single display
setDecimalOnOff(uint8_t displayNumber, bool turnOnDecimal); --- Set or clear the decimal ‎on/off bit
colonOn(); --- Turn the colon on for all displays on the bus
colonOff(); --- Turn the colon off for all displays on the bus
colonOnSingle(uint8_t displayNumber); --- Turn the colon on for a single display
colonOffSingle(uint8_t displayNumber); --- Turn the colon off for a single display
setColonOnOff(uint8_t displayNumber, bool turnOnColon); --- Set or clear the colon on/off ‎bit
shiftRight(uint8_t shiftAmt = 1); --- Shift the display content to the right one digit
shiftLeft(uint8_t shiftAmt = 1); --- Shift the display content to the left one digit

Arduino Examples - The Basics

Now that we have our library installed, we're ready to run some examples. The library currently ‎comes with a set of 10 examples to get you started on your way. Let's look at the first few examples!‎

Example_01_PrintString

Once the library is installed, go ahead, and open up File->Examples->SparkFun Qwiic ‎Alphanumeric Display Library->Example_01_PrintString.‎

Alternatively, you can copy and paste the code below to a shiny new Arduino file:‎

Copy Code

    language:c
/*****************************************************************************************
 * This example tests illuminating whole 4 letter strings on the 14-segment display.
 * 
 * Priyanka Makin @ SparkFun Electronics
 * Original Creation Date: February 3, 2020
 * 
 * SparkFun labored with love to create this code. Feel like supporting open source hardware?
 * Buy a board from SparkFun! https://www.sparkfun.com/products/16391
 * 
 * This code is Lemonadeware; if you see me (or any other SparkFun employee) at the 
 * local, and you've found our code helpful, please buy us a round!
 * 
 * Hardware Connections:
 * Attach Red Board to computer using micro-B USB cable.
 * Attach Qwiic Alphanumeric board to Red Board using Qwiic cable.
 * 
 * Distributed as-is; no warranty is given.
 ****************************************************************************************/
#include <Wire.h>

#include <SparkFun_Alphanumeric_Display.h> //Click here to get the library: http://librarymanager/All#SparkFun_Qwiic_Alphanumeric_Display by SparkFun
HT16K33 display;

void setup()
{
  Serial.begin(115200);
  Serial.println("SparkFun Qwiic Alphanumeric - Example 1: Print String");

  Wire.begin(); //Join I2C bus

  if (display.begin() == false)
  {
    Serial.println("Device did not acknowledge! Freezing.");
    while (1);
  }
  Serial.println("Display acknowledged.");

  display.print("Milk");
}

void loop()
{
}

Once you have the code, make sure you've got the correct port selected, and then go ahead and ‎click on the upload button. If all goes well, you'll see your Display light up with "Milk"!‎

port_13

Example_02_TurnOnOneSegment

This example lights up a single segment on the display. Head on back to your File Menu and open ‎up File->Examples->SparkFun Qwiic Alphanumeric Display Library-‎‎>Example_02_TurnOnOneSegment.‎

Alternatively, you can copy and paste the code below to a shiny new Arduino file:‎

Copy Code

/*******************************************************************************************
 * This example tests illuminating individual segments of the display. Pass in the segment
 * and digit you wish to illuminate to illuminateSegement().
 * 
 * Priyanka Makin @ SparkFun Electronics
 * Original Creation Date: January 31, 2020
 * 
 * SparkFun labored with love to create this code. Feel like supporting open source hardware?
 * Buy a board from SparkFun! https://www.sparkfun.com/products/16391
 * 
 * This code is Lemonadeware; if you see me (or any other SparkFun employee) at the 
 * local, and you've found our code helpful, please buy us a round!
 * 
 * Hardware Connections:
 * Attach Red Board to computer using micro-B USB cable.
 * Attach Qwiic Alphanumeric board to Red Board using Qwiic cable.
 * 
 * Distributed as-is; no warranty is given.
 *****************************************************************************************/
#include <Wire.h>

#include <SparkFun_Alphanumeric_Display.h>  //Click here to get the library: http://librarymanager/All#SparkFun_Qwiic_Alphanumeric_Display by SparkFun
HT16K33 display;

void setup()
{
  Serial.begin(115200);
  Serial.println("SparkFun Qwiic Alphanumeric - Example 2: Turn On One Segment");
  Wire.begin(); //Join I2C bus

  //check if display will acknowledge
  if (display.begin() == false)
  {
    Serial.println("Device did not acknowledge! Freezing.");
    while(1);
  }
  Serial.println("Display acknowledged.");

  display.illuminateSegment('A', 0);
  display.illuminateSegment('L', 1);
  display.illuminateSegment('I', 2);
  display.illuminateSegment('G', 3);
  display.updateDisplay();
}

void loop()
{
}

As before, once you have the code, make sure you've got the correct port selected, and then go ‎ahead and click on the upload button. You won't need your serial monitor for this one though, ‎unless you want it. If all goes well, you should see your display light up like so:‎

code_14

It looks weird, but it's one segment of each letter lit up.‎

Example_03_PrintChar

Let's print some stuff! Grab Example 3 by going to File->Examples->SparkFun Qwiic ‎Alphanumeric Display Library->Example_03_PrintChar.‎

Alternatively, you can copy and paste the code below to a shiny new Arduino file:‎

Copy Code

/*****************************************************************************************
 * This example tests illuminating whole characters on the 14-segment display.
 * 
 * Priyanka Makin @ SparkFun Electronics
 * Original Creation Date: February 3, 2020
 * 
 * SparkFun labored with love to create this code. Feel like supporting open source hardware?
 * Buy a board from SparkFun! https://www.sparkfun.com/products/16391
 * 
 * This code is Lemonadeware; if you see me (or any other SparkFun employee) at the
 * local, and you've found our code helpful, please buy us a round!
 * 
 * Hardware Connections:
 * Attach Red Board to computer using micro-B USB cable.
 * Attach Qwiic Alphanumeric board to Red Board using Qwiic cable.
 * 
 * Distributed as-is; no warranty is given.
 *****************************************************************************************/
#include <Wire.h>

#include <SparkFun_Alphanumeric_Display.h>  //Click here to get the library: http://librarymanager/All#SparkFun_Qwiic_Alphanumeric_Display by SparkFun
HT16K33 display;

void setup()
{
  Serial.begin(115200);
  Serial.println("SparkFun Qwiic Alphanumeric - Example 3: Print Character");
  Wire.begin(); //Join I2C bus

  //check if display will acknowledge
  if (display.begin() == false)
  {
    Serial.println("Device did not acknowledge! Freezing.");
    while(1);
  }
  Serial.println("Display acknowledged.");

  display.printChar('W', 0);
  display.printChar('H', 1);
  display.printChar('A', 2);
  display.printChar('T', 3);

  display.updateDisplay();
}

void loop(){
}

Check your port, and then click on the upload button. Voila! Are you starting to get the picture?‎

button_15

This is just the beginning - there are more examples to get you going with your SparkFun Qwiic ‎Alphanumeric Display. We won't go through them all here, but feel free to tinker with these to see ‎what all you can come up with!‎

If you haven't downloaded the library yet, get it either here or by clicking on the link below and get ‎hackin!‎

DOWNLOAD THE SPARKFUN ALPHANUMERIC DISPLAY ARDUINO LIBRARY (ZIP)‎

Arduino Examples - The Fun Stuff

Okay. You got the basics done - you can light up segments, yes? Now let’s do a couple of fun ‎things!‎

Example_08_MultiDisplay

This example tests printing across multiple displays. In order to make this example work, you'll need ‎to do some soldering on the jumpers on the back of the board. For this example, we'll use 0x70 and ‎‎0x71 as the addresses, so the jumpers for the second display should look like this:‎

test_16

Once your jumper is soldered, go ahead, and hook your boards together with your Qwiic cables and ‎plug them on into your RedBoard.‎

hook_17

Once your hardware is ready to go, head back to your File Menu and open up File->Examples-‎‎>SparkFun Qwiic Alphanumeric Display Library->Example_08_MultiDisplay.‎

Alternatively, you can copy and paste the code below to a shiny new Arduino file:‎

Copy Code

/**************************************************************************************
 * This example tests printing across multiple alpha displays.
 * 
 * Priyanka Makin @ SparkFun Electronics
 * Original Creation Date: February 26, 2020
 * 
 * SparkFun labored with love to create this code. Feel like supporting open source hardware?
 * Buy a board from SparkFun! https://www.sparkfun.com/products/16391
 * 
 * This code is Lemonadeware; if you see me (or any other SparkFun employee) at the
 * local, and you've found our code helpful, please buy us a round!
 * 
 * Hardware Connections:
 * Attach Red Board to computer using micro-B USB cable.
 * Attach Qwiic Alphanumeric board to Red Board using Qwiic cable. 
 *  Don't close any of the address jumpers so that it defaults to address 0x70.
 * Attach a second Alphanumeric display using Qwiic cable.
 *  Close address jumper A0 so that this display's address become 0x71.
 * 
 * Distributed as-is; no warranty is given.
 *****************************************************************************************/
#include <Wire.h>

#include <SparkFun_Alphanumeric_Display.h>  //Click here to get the library: http://librarymanager/All#SparkFun_Qwiic_Alphanumeric_Display by SparkFun
HT16K33 display;

void setup() {
  Serial.begin(115200);
  Serial.println("SparkFun Qwiic Alphanumeric - Example 8: Multi Display");
  Wire.begin(); //Join I2C bus

  //check if displays will acknowledge
  //The first address in the begin() function should be the left-most display, traveling to the right from there
  //This is how the string will print across displays, reading from left to right.
  if (display.begin(0x70, 0x71) == false)
  {
    Serial.println("Device did not acknowledge! Freezing.");
    while(1);
  }
  Serial.println("Displays acknowledged.");

  display.print("Get Milk");
}

void loop() 
{
}

Once you've got your code, make sure you've got the correct port selected, and then go ahead and ‎click on the upload button. You should see the following:‎

select_18

Example_09_ScrollingString

This example SCROLLS! Let's start by plugging your Alphanumeric board into your RedBoard with ‎your handy dandy Qwiic cables.‎

Once your hardware is ready to go, head back to your File Menu and open File->Examples-‎‎>SparkFun Qwiic Alphanumeric Display Library->Example_09_ScrollingString.‎

Alternatively, you can copy and paste the code below to a shiny new Arduino file:‎

Copy Code

/**************************************************************************************
 * This example tests scrolling functionality of alphanumeric displays.
 * 
 * Priyanka Makin @ SparkFun Electronics
 * Original Creation Date: February 26, 2020
 * 
 * SparkFun labored with love to create this code. Feel like supporting open source hardware?
 * Buy a board from SparkFun! https://www.sparkfun.com/products/16391
 * 
 * This code is Lemonadeware; if you see me (or any other SparkFun employee) at the
 * local, and you've found our code helpful, please buy us a round!
 * 
 * Hardware Connections:
 * Attach Red Board to computer using micro-B USB cable.
 * Attach Qwiic Alphanumeric board to Red Board using Qwiic cable. 
 *  Don't close any of the address jumpers so that it defaults to address 0x70.
 * Attach a second Alphanumeric display using Qwiic cable.
 *  Close address jumper A0 so that this display's address become 0x71.
 * 
 * Distributed as-is; no warranty is given.
 *****************************************************************************************/
#include <Wire.h>

#include <SparkFun_Alphanumeric_Display.h>  //Click here to get the library: http://librarymanager/All#SparkFun_Qwiic_Alphanumeric_Display by SparkFun
HT16K33 display;

void setup() {
  Serial.begin(115200);
  Serial.println("SparkFun Qwiic Alphanumeric - Example 9: Scrolling String");
  Wire.begin(); //Join I2C bus

  //check if displays will acknowledge
  if (display.begin(0x70) == false)
  {
    Serial.println("Device did not acknowledge! Freezing.");
    while(1);
  }
  Serial.println("Display acknowledged.");

  display.print("MILK");
}

void loop() 
{  
  delay(300);
  display.shiftLeft();
  //Alternatively - you could also shift the string to the right
  //display.shiftRight();
}

Once you've got your code, make sure you've got the correct port selected, and then go ahead and ‎click on the upload button. You should see the following:‎

upload_19

Troubleshooting

Not working as expected and need help? ‎

If you need technical assistance and more information on a product that is not working as you ‎expected, we recommend heading on over to the SparkFun Technical Assistance page for some ‎initial troubleshooting.

SPARKFUN TECHNICAL ASSISTANCE PAGE‎ ‎

If you don't find what you need there, the SparkFun Forums are a great place to find and ask for ‎help. If this is your first visit, you'll need to create a Forum Account to search product forums and ‎post questions.

CREATE NEW FORUM ACCOUNT LOG INTO SPARKFUN FORUMS

Resources and Going Further

Congratulations! Now that you've got your Alphanumeric Display(s) up and running, you can hack ‎that boring ol' microwave message with something more "fool" proof! YES!‎

If you want or need information on your Alphanumeric Display, check out some of the resources ‎below:‎