Grove - 4-Digit Display

Introduction

Grove - 4-Digit Display module is a 12-pin module. In this module, we utilise a TM1637 to scale down the number of controlling pins to 2. That is to say, it controls both the content and the luminance via only 2 digital pins of Arduino or Seeeduino. For projects that require alpha-numeric display, this can be a nice choice.

Features

• 4 digit red alpha-numeric display
• Grove compatible interface (3.3V/5V)
• 8 adjustable luminance levels

Application Ideas

• Time display
• Stopwatch
• Sensors’ input display

Specifications

Item	Min	Typical	Max	Unit
Voltage	3.3	5.0	5.5	VDC
Current	0.2	27	80	mA
Dimensions	42x24x14			mm
Net Weight	7±1			g

Platforms Supported

Hardware Overview

Grove interface - Can be connected to digital port on Grove - Base Shield.

4 - digit display - Common anode digital tube.

Pin definition: CLK DIO VCC GND

Getting Started

With TI LaunchPad

Displaying the Numbers (4-Digital-Display)

This example demonstrates how to display some digital numbers using a Grove-4-Digital Display.

/*
 * TM1637.cpp
 * A library for the 4 digit display
 */
#include "TM1637.h"
#define CLK 39 //pins definitions for TM1637 and can be changed to other ports
#define DIO 38
TM1637 tm1637(CLK,DIO);
void setup()
{
    tm1637.init();
    tm1637.set(BRIGHT_TYPICAL);//BRIGHT_TYPICAL = 2,BRIGHT_DARKEST = 0,BRIGHTEST = 7;
}
void loop()
{
    int8_t NumTab[] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};//0~9,A,b,C,d,E,F
    int8_t ListDisp[4];
    unsigned char i = 0;
    unsigned char count = 0;
    delay(150);
    while(1)
    {
        i = count;
        count ++;
        if(count == sizeof(NumTab)) count = 0;
        for(unsigned char BitSelect = 0;BitSelect < 4;BitSelect ++)
        {
            ListDisp[BitSelect] = NumTab[i];
            i ++;
            if(i == sizeof(NumTab)) i = 0;
        }
        tm1637.display(0,ListDisp[0]);
        tm1637.display(1,ListDisp[1]);
        tm1637.display(2,ListDisp[2]);
        tm1637.display(3,ListDisp[3]);
        delay(300);
    }
}

With Arduino

The module uses an LED drive chip - TM1637 to control the contents and change the luminance. Here we drive it to display time.

1. Connect the Grove socket marked “IN” on the LED Strip Driver and digital port 2 of the Grove - Base Shield with a Grove cable. You can change to the digital port as you like. But don’t forget to change the port number in the definition of the demo code at the same time.

2. Plug onto Arduino/Seeeduino or plug Grove - Mega Shield onto Arduino Mega.

   Seeeduino and Grove - 4-digit display:

   

   Arduino Mega and Grove - 4-digit display:

3. Connect Arduino/Seeeduino to PC via a USB cable.

4. Download the 4-Digit Display library and TimerOne library. Unzip and put them in the libraries file of Arduino IDE by the path: ..\arduino-1.0\libraries.

5. Restart the Arduino IDE, open one demo code you like, for example ClockDisplay directly by the path:File -> Example ->DigitalTube->ClockDisplay.

   

6. Upload the demo code and the clock will be ticking in a few seconds.

   You can see this:

With Raspberry Pi

1.You should have got a raspberry pi and a grovepi or grovepi+.

2.You should have completed configuring the development enviroment, otherwise follow here.

3.Connection

• Plug the sensor to grovepi socket D5 by using a grove cable.

4.Navigate to the demos’ directory:

cd yourpath/GrovePi/Software/Python/

• To see the code

nano grove_4_digit_display.py   # "Ctrl+x" to exit #

    import time
    import grovepi

    # Connect the Grove 4 Digit Display to digital port D5
    # CLK,DIO,VCC,GND
    display = 5
    grovepi.pinMode(display,"OUTPUT")

    # If you have an analog sensor connect it to A0 so you can monitor it below
    sensor = 0
    grovepi.pinMode(sensor,"INPUT")

    time.sleep(.5)

    # 4 Digit Display methods
    # grovepi.fourDigit_init(pin)
    # grovepi.fourDigit_number(pin,value,leading_zero)
    # grovepi.fourDigit_brightness(pin,brightness)
    # grovepi.fourDigit_digit(pin,segment,value)
    # grovepi.fourDigit_segment(pin,segment,leds)
    # grovepi.fourDigit_score(pin,left,right)
    # grovepi.fourDigit_monitor(pin,analog,duration)
    # grovepi.fourDigit_on(pin)
    # grovepi.fourDigit_off(pin)

    while True:
        try:
            print "Test 1) Initialise"
            grovepi.fourDigit_init(display)
            time.sleep(.5)

            print "Test 2) Set brightness"
            for i in range(0,8):
                grovepi.fourDigit_brightness(display,i)
                time.sleep(.2)
            time.sleep(.3)

            # set to lowest brightness level
            grovepi.fourDigit_brightness(display,0)
            time.sleep(.5)

            print "Test 3) Set number without leading zeros"
            leading_zero = 0
            grovepi.fourDigit_number(display,1,leading_zero)
            time.sleep(.5)
            grovepi.fourDigit_number(display,12,leading_zero)
            time.sleep(.5)
            grovepi.fourDigit_number(display,123,leading_zero)
            time.sleep(.5)
            grovepi.fourDigit_number(display,1234,leading_zero)
            time.sleep(.5)

            print "Test 4) Set number with leading zeros"
            leading_zero = 1
            grovepi.fourDigit_number(display,5,leading_zero)
            time.sleep(.5)
            grovepi.fourDigit_number(display,56,leading_zero)
            time.sleep(.5)
            grovepi.fourDigit_number(display,567,leading_zero)
            time.sleep(.5)
            grovepi.fourDigit_number(display,5678,leading_zero)
            time.sleep(.5)

            print "Test 5) Set individual digit"
            grovepi.fourDigit_digit(display,0,2)
            grovepi.fourDigit_digit(display,1,6)
            grovepi.fourDigit_digit(display,2,9)
            grovepi.fourDigit_digit(display,3,15) # 15 = F
            time.sleep(.5)

            print "Test 6) Set individual segment"
            grovepi.fourDigit_segment(display,0,118) # 118 = H
            grovepi.fourDigit_segment(display,1,121) # 121 = E
            grovepi.fourDigit_segment(display,2,118) # 118 = H
            grovepi.fourDigit_segment(display,3,121) # 121 = E
            time.sleep(.5)

            grovepi.fourDigit_segment(display,0,57) # 57 = C
            grovepi.fourDigit_segment(display,1,63) # 63 = O
            grovepi.fourDigit_segment(display,2,63) # 63 = O
            grovepi.fourDigit_segment(display,3,56) # 56 = L
            time.sleep(.5)

            print "Test 7) Set score"
            grovepi.fourDigit_score(display,0,0)
            time.sleep(.2)
            grovepi.fourDigit_score(display,1,0)
            time.sleep(.2)
            grovepi.fourDigit_score(display,1,1)
            time.sleep(.2)
            grovepi.fourDigit_score(display,1,2)
            time.sleep(.2)
            grovepi.fourDigit_score(display,1,3)
            time.sleep(.2)
            grovepi.fourDigit_score(display,1,4)
            time.sleep(.2)
            grovepi.fourDigit_score(display,1,5)
            time.sleep(.5)

            print "Test 8) Set time"
            grovepi.fourDigit_score(display,12,59)
            time.sleep(.5)

            print "Test 9) Monitor analog pin"
            seconds = 10
            grovepi.fourDigit_monitor(display,sensor,seconds)
            time.sleep(.5)

            print "Test 10) Switch all on"
            grovepi.fourDigit_on(display)
            time.sleep(.5)

            print "Test 11) Switch all off"
            grovepi.fourDigit_off(display)
            time.sleep(.5)

        except KeyboardInterrupt:
            grovepi.fourDigit_off(display)
            break
        except IOError:
            print "Error"

5.Run the demo.

sudo python grove_4_digit_display.py

6.This demo may not work if your grovepi doesn’t have the newest firmware, update the firmware.

cd yourpath/GrovePi/Firmware
sudo ./firmware_update.sh

Project

Inspired by OVERWATCH, we have made a very cool Wooden Laser Gun toy for fun these day!

The Wooden Laser Gun and the Gun Target are all based on an Arduino board called Seeeduino Lotus. The laser emitter on the Laser Gun is controlled to fire laser pulse to “activate” the Gun Target. And there are 3 light sensors on the Gun Target to detect the laser pulse. It seems very simple right? If you are interested in our project, please make one for yourself or your child! It’s worth to spend one day DIY it as a Xmas present.

Resources

• Grove - 4-Digit Display V1.0 eagle files
• Schematic in PDF
• 4-Digit Display library
• TimerOne library
• Four-Digit Display Suli Library
• TM1637 datasheet

Help us make it better

Welcome to the new documentation system of Seeed Studio. We have made a lot of progress comparing to the old wiki system and will continue to improve it to make it more user friendly and helpful. The improvement can't be done without your kindly feedback. If you have any suggestions or findings, you are most welcome to submit the amended version as our contributor via Github or give us suggestions in the survey below, it would be more appreciated if you could leave your email so that we can reply to you. Happy Hacking!