7segment led display with raspberry pi pico micropython tutorial

7-Segment LED Display With Raspberry PI Pico Using Micropython

Table of Contents

This is a guide on how to use a TM1637 4-Digit 7-Segment LED Display With Raspberry PI Pico using Micropython. We’ll go over how to connect the display, how to control it using Micropython, and finally how to create a simple watch program.

Required materials

You will need the following materials: –

Raspberry Pi Pico –
7-segment LED display –
Jumper wires –

7-segment LED display

A TM1637 4-Digit 7-segment LED display is a type of electronic display used to show information in numerical form. They are often used in electronic devices such as clocks, calculators, and radios.

The TM1637 display is an excellent method to add numerical information to an electronic project. These displays are easy to use and deliver a clear and straightforward way to display numbers. By following a few easy guidelines, anyone can use a TM1637 display to add numerical information to their project.

The module works between 3.3V to 5V with a current consumption of 80mA. We can interface TM1637 with Raspberry Pi Pico or any different microcontroller operating the two data pins. There is a committed MicroPython Library for TM1637 that removes the complexity and drives it more straightforwardly to communicate with the display.

TM1637 Module Pinout

Pinouts :

CLK: Clock Input Pin
DIO: Data Input/Output Pin
VCC: 3.3V to 5V power supply Pin
GND: Clock Input Pin

Raspberry Pi Pico

Raspberry Pi Pico is a low-cost, high-performance microcontroller board with flexible digital interfaces. It is developed for makers, teachers, and anyone interested in creating interactive applications that control physical systems. With its low price, small size, and comfort of use, the Raspberry Pi Pico is perfect for anyone who wants to get started with coding and hardware interfacing. Before we used Raspberry Pi Pico to build many Projects.

Raspberry Pi Pico Pinout

How to Connect TM1637 Module With Raspberry Pi Pico

Connect the ground (GND) pin on the TM1637 module to the ground (GND) pin on the pi pico. Then, connect the power (VCC) pin on the TM1637 module to the power (5V) pin on the Pico. Now, connect the data (DIO) pin on the TM1637 module to the GPIO Pin 1 pin on the Pico. Finally, connect the clock (CLK) pin on the TM1637 module to the 0 pin of the Raspberry Pi Pico respectively.

MicroPython Script

The TM1637 requires a MicroPython library for interfacing with Raspberry Pi Pico. Accordingly, we have codes here as “tm1637.py” & “text.py“.

tm1637.py

"""
MicroPython TM1637 quad 7-segment LED display driver
https://github.com/mcauser/micropython-tm1637

MIT License
Copyright (c) 2016 Mike Causer

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
"""

from micropython import const
from machine import Pin
from time import sleep_us, sleep_ms

TM1637_CMD1 = const(64)  # 0x40 data command
TM1637_CMD2 = const(192) # 0xC0 address command
TM1637_CMD3 = const(128) # 0x80 display control command
TM1637_DSP_ON = const(8) # 0x08 display on
TM1637_DELAY = const(10) # 10us delay between clk/dio pulses
TM1637_MSB = const(128)  # msb is the decimal point or the colon depending on your display

# 0-9, a-z, blank, dash, star
_SEGMENTS = bytearray(b'\x3F\x06\x5B\x4F\x66\x6D\x7D\x07\x7F\x6F\x77\x7C\x39\x5E\x79\x71\x3D\x76\x06\x1E\x76\x38\x55\x54\x3F\x73\x67\x50\x6D\x78\x3E\x1C\x2A\x76\x6E\x5B\x00\x40\x63')

class TM1637(object):
    """Library for quad 7-segment LED modules based on the TM1637 LED driver."""
    def __init__(self, clk, dio, brightness=7):
        self.clk = clk
        self.dio = dio

        if not 0 <= brightness <= 7:
            raise ValueError("Brightness out of range")
        self._brightness = brightness

        self.clk.init(Pin.OUT, value=0)
        self.dio.init(Pin.OUT, value=0)
        sleep_us(TM1637_DELAY)

        self._write_data_cmd()
        self._write_dsp_ctrl()

    def _start(self):
        self.dio(0)
        sleep_us(TM1637_DELAY)
        self.clk(0)
        sleep_us(TM1637_DELAY)

    def _stop(self):
        self.dio(0)
        sleep_us(TM1637_DELAY)
        self.clk(1)
        sleep_us(TM1637_DELAY)
        self.dio(1)

    def _write_data_cmd(self):
        # automatic address increment, normal mode
        self._start()
        self._write_byte(TM1637_CMD1)
        self._stop()

    def _write_dsp_ctrl(self):
        # display on, set brightness
        self._start()
        self._write_byte(TM1637_CMD3 | TM1637_DSP_ON | self._brightness)
        self._stop()

    def _write_byte(self, b):
        for i in range(8):
            self.dio((b >> i) & 1)
            sleep_us(TM1637_DELAY)
            self.clk(1)
            sleep_us(TM1637_DELAY)
            self.clk(0)
            sleep_us(TM1637_DELAY)
        self.clk(0)
        sleep_us(TM1637_DELAY)
        self.clk(1)
        sleep_us(TM1637_DELAY)
        self.clk(0)
        sleep_us(TM1637_DELAY)

    def brightness(self, val=None):
        """Set the display brightness 0-7."""
        # brightness 0 = 1/16th pulse width
        # brightness 7 = 14/16th pulse width
        if val is None:
            return self._brightness
        if not 0 <= val <= 7:
            raise ValueError("Brightness out of range")

        self._brightness = val
        self._write_data_cmd()
        self._write_dsp_ctrl()

    def write(self, segments, pos=0):
        """Display up to 6 segments moving right from a given position.
        The MSB in the 2nd segment controls the colon between the 2nd
        and 3rd segments."""
        if not 0 <= pos <= 5:
            raise ValueError("Position out of range")
        self._write_data_cmd()
        self._start()

        self._write_byte(TM1637_CMD2 | pos)
        for seg in segments:
            self._write_byte(seg)
        self._stop()
        self._write_dsp_ctrl()

    def encode_digit(self, digit):
        """Convert a character 0-9, a-f to a segment."""
        return _SEGMENTS[digit & 0x0f]

    def encode_string(self, string):
        """Convert an up to 4 character length string containing 0-9, a-z,
        space, dash, star to an array of segments, matching the length of the
        source string."""
        segments = bytearray(len(string))
        for i in range(len(string)):
            segments[i] = self.encode_char(string[i])
        return segments

    def encode_char(self, char):
        """Convert a character 0-9, a-z, space, dash or star to a segment."""
        o = ord(char)
        if o == 32:
            return _SEGMENTS[36] # space
        if o == 42:
            return _SEGMENTS[38] # star/degrees
        if o == 45:
            return _SEGMENTS[37] # dash
        if o >= 65 and o <= 90:
            return _SEGMENTS[o-55] # uppercase A-Z
        if o >= 97 and o <= 122:
            return _SEGMENTS[o-87] # lowercase a-z
        if o >= 48 and o <= 57:
            return _SEGMENTS[o-48] # 0-9
        raise ValueError("Character out of range: {:d} '{:s}'".format(o, chr(o)))

    def hex(self, val):
        """Display a hex value 0x0000 through 0xffff, right aligned."""
        string = '{:04x}'.format(val & 0xffff)
        self.write(self.encode_string(string))

    def number(self, num):
        """Display a numeric value -999 through 9999, right aligned."""
        # limit to range -999 to 9999
        num = max(-999, min(num, 9999))
        string = '{0: >4d}'.format(num)
        self.write(self.encode_string(string))

    def numbers(self, num1, num2, colon=True):
        """Display two numeric values -9 through 99, with leading zeros
        and separated by a colon."""
        num1 = max(-9, min(num1, 99))
        num2 = max(-9, min(num2, 99))
        segments = self.encode_string('{0:0>2d}{1:0>2d}'.format(num1, num2))
        if colon:
            segments[1] |= 0x80 # colon on
        self.write(segments)

    def temperature(self, num):
        if num < -9:
            self.show('lo') # low
        elif num > 99:
            self.show('hi') # high
        else:
            string = '{0: >2d}'.format(num)
            self.write(self.encode_string(string))
        self.write([_SEGMENTS[38], _SEGMENTS[12]], 2) # degrees C

    def show(self, string, colon=False):
        segments = self.encode_string(string)
        if len(segments) > 1 and colon:
            segments[1] |= 128
        self.write(segments[:4])

    def scroll(self, string, delay=250):
        segments = string if isinstance(string, list) else self.encode_string(string)
        data = [0] * 8
        data[4:0] = list(segments)
        for i in range(len(segments) + 5):
            self.write(data[0+i:4+i])
            sleep_ms(delay)


class TM1637Decimal(TM1637):
    """Library for quad 7-segment LED modules based on the TM1637 LED driver.

    This class is meant to be used with decimal display modules (modules
    that have a decimal point after each 7-segment LED).
    """

    def encode_string(self, string):
        """Convert a string to LED segments.

        Convert an up to 4 character length string containing 0-9, a-z,
        space, dash, star and '.' to an array of segments, matching the length of
        the source string."""
        segments = bytearray(len(string.replace('.','')))
        j = 0
        for i in range(len(string)):
            if string[i] == '.' and j > 0:
                segments[j-1] |= TM1637_MSB
                continue
            segments[j] = self.encode_char(string[i])
            j += 1
        return segments

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"""

MicroPython TM1637 quad 7-segment LED display driver

https://github.com/mcauser/micropython-tm1637

MIT License

Permission is hereby granted, free of charge, to any person obtaining a copy

of this software and associated documentation files (the "Software"), to deal

in the Software without restriction, including without limitation the rights

to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

copies of the Software, and to permit persons to whom the Software is

furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all

copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE

SOFTWARE.

"""

from micropython import const

from machine import Pin

from time import sleep_us, sleep_ms

TM1637_CMD1 = const(64) # 0x40 data command

TM1637_CMD2 = const(192) # 0xC0 address command

TM1637_CMD3 = const(128) # 0x80 display control command

TM1637_DSP_ON = const(8) # 0x08 display on

TM1637_DELAY = const(10) # 10us delay between clk/dio pulses

TM1637_MSB = const(128) # msb is the decimal point or the colon depending on your display

# 0-9, a-z, blank, dash, star

_SEGMENTS = bytearray(b'\x3F\x06\x5B\x4F\x66\x6D\x7D\x07\x7F\x6F\x77\x7C\x39\x5E\x79\x71\x3D\x76\x06\x1E\x76\x38\x55\x54\x3F\x73\x67\x50\x6D\x78\x3E\x1C\x2A\x76\x6E\x5B\x00\x40\x63')

class TM1637(object):

"""Library for quad 7-segment LED modules based on the TM1637 LED driver."""

def __init__(self, clk, dio, brightness=7):

self.clk = clk

self.dio = dio

if not 0 <= brightness <= 7:

raise ValueError("Brightness out of range")

self._brightness = brightness

self.clk.init(Pin.OUT, value=0)

self.dio.init(Pin.OUT, value=0)

sleep_us(TM1637_DELAY)

self._write_data_cmd()

self._write_dsp_ctrl()

def _start(self):

self.dio(0)

sleep_us(TM1637_DELAY)

self.clk(0)

sleep_us(TM1637_DELAY)

def _stop(self):

self.dio(0)

sleep_us(TM1637_DELAY)

self.clk(1)

sleep_us(TM1637_DELAY)

self.dio(1)

def _write_data_cmd(self):

# automatic address increment, normal mode

self._start()

self._write_byte(TM1637_CMD1)

self._stop()

def _write_dsp_ctrl(self):

# display on, set brightness

self._start()

self._write_byte(TM1637_CMD3 | TM1637_DSP_ON | self._brightness)

self._stop()

def _write_byte(self, b):

for i in range(8):

self.dio((b >> i) & 1)

sleep_us(TM1637_DELAY)

self.clk(1)

sleep_us(TM1637_DELAY)

self.clk(0)

sleep_us(TM1637_DELAY)

self.clk(0)

sleep_us(TM1637_DELAY)

self.clk(1)

sleep_us(TM1637_DELAY)

self.clk(0)

sleep_us(TM1637_DELAY)

def brightness(self, val=None):

"""Set the display brightness 0-7."""

# brightness 0 = 1/16th pulse width

# brightness 7 = 14/16th pulse width

if val is None:

return self._brightness

if not 0 <= val <= 7:

raise ValueError("Brightness out of range")

self._brightness = val

self._write_data_cmd()

self._write_dsp_ctrl()

def write(self, segments, pos=0):

"""Display up to 6 segments moving right from a given position.

The MSB in the 2nd segment controls the colon between the 2nd

and 3rd segments."""

if not 0 <= pos <= 5:

raise ValueError("Position out of range")

self._write_data_cmd()

self._start()

self._write_byte(TM1637_CMD2 | pos)

for seg in segments:

self._write_byte(seg)

self._stop()

self._write_dsp_ctrl()

def encode_digit(self, digit):

"""Convert a character 0-9, a-f to a segment."""

return _SEGMENTS[digit & 0x0f]

def encode_string(self, string):

"""Convert an up to 4 character length string containing 0-9, a-z,

space, dash, star to an array of segments, matching the length of the

source string."""

segments = bytearray(len(string))

for i in range(len(string)):

segments[i] = self.encode_char(string[i])

return segments

def encode_char(self, char):

"""Convert a character 0-9, a-z, space, dash or star to a segment."""

o = ord(char)

if o == 32:

return _SEGMENTS[36] # space

if o == 42:

return _SEGMENTS[38] # star/degrees

if o == 45:

return _SEGMENTS[37] # dash

if o >= 65 and o <= 90:

return _SEGMENTS[o-55] # uppercase A-Z

if o >= 97 and o <= 122:

return _SEGMENTS[o-87] # lowercase a-z

if o >= 48 and o <= 57:

return _SEGMENTS[o-48] # 0-9

raise ValueError("Character out of range: {:d} '{:s}'".format(o, chr(o)))

def hex(self, val):

"""Display a hex value 0x0000 through 0xffff, right aligned."""

string = '{:04x}'.format(val & 0xffff)

self.write(self.encode_string(string))

def number(self, num):

"""Display a numeric value -999 through 9999, right aligned."""

# limit to range -999 to 9999

num = max(-999, min(num, 9999))

string = '{0: >4d}'.format(num)

self.write(self.encode_string(string))

def numbers(self, num1, num2, colon=True):

"""Display two numeric values -9 through 99, with leading zeros

and separated by a colon."""

num1 = max(-9, min(num1, 99))

num2 = max(-9, min(num2, 99))

segments = self.encode_string('{0:0>2d}{1:0>2d}'.format(num1, num2))

if colon:

segments[1] |= 0x80 # colon on

self.write(segments)

def temperature(self, num):

if num < -9:

self.show('lo') # low

elif num > 99:

self.show('hi') # high

else:

string = '{0: >2d}'.format(num)

self.write(self.encode_string(string))

self.write([_SEGMENTS[38], _SEGMENTS[12]], 2) # degrees C

def show(self, string, colon=False):

segments = self.encode_string(string)

if len(segments) > 1 and colon:

segments[1] |= 128

self.write(segments[:4])

def scroll(self, string, delay=250):

segments = string if isinstance(string, list) else self.encode_string(string)

data = [0] * 8

data[4:0] = list(segments)

for i in range(len(segments) + 5):

self.write(data[0+i:4+i])

sleep_ms(delay)

class TM1637Decimal(TM1637):

"""Library for quad 7-segment LED modules based on the TM1637 LED driver.

This class is meant to be used with decimal display modules (modules

that have a decimal point after each 7-segment LED).

"""

def encode_string(self, string):

"""Convert a string to LED segments.

Convert an up to 4 character length string containing 0-9, a-z,

space, dash, star and '.' to an array of segments, matching the length of

the source string."""

segments = bytearray(len(string.replace('.','')))

j = 0

for i in range(len(string)):

if string[i] == '.' and j > 0:

segments[j-1] |= TM1637_MSB

continue

segments[j] = self.encode_char(string[i])

j += 1

return segments

text.py

This Micropython code for scrolling text on Display

import tm1637
from machine import Pin
from utime import sleep
mydisplay = tm1637.TM1637(clk=Pin(0), dio=Pin(1))
#adjust the brightness 
mydisplay.brightness(1)
sleep(1) 
# Show a word
mydisplay.show("Zeba")
sleep(1)

#show scrolling text
mydisplay.scroll(" PROJECTS LAB ", delay=300)

import tm1637

from machine import Pin

from utime import sleep

mydisplay = tm1637.TM1637(clk=Pin(0), dio=Pin(1))

#adjust the brightness

mydisplay.brightness(1)

sleep(1)

# Show a word

mydisplay.show("Zeba")

sleep(1)

#show scrolling text

mydisplay.scroll(" PROJECTS LAB ", delay=300)

time.py

if you want to use your display as Electronic Clock Use this Micropython code for the clock.

#diyprojectslab.com

import tm1637
from machine import Pin
from utime import sleep
tm = tm1637.TM1637(clk=Pin(0), dio=Pin(1))

Hour = 07  #Set Real Time hour
Min = 05   #Set Real Time Minute
Sec = 35   #Set Real Time Second


if __name__ == '__main__':
    while True:
        tm.numbers(Hour,Min,colon=True)
        sleep(0.5)
        tm.numbers(Hour,Min,colon=False)
        sleep(0.5)
        Sec = Sec + 1
        if Sec == 60:
            Min = Min + 1
            Sec = 0           
            if Min == 60:
                Hour = Hour + 1
                Min = 0
                if Hour == 24:
                    Hour = 0