In this article we connect a TM1637 display module to a Raspberry Pi Pico and we will have some examples in Micropython

Module Information

A common display module that you can buy on the internet contain the Tm1638 driver chip, I was interested in this one which is the TM1637 which appears to be a more basic version which can only control a display, the TM1638 can also control LED’s, buttons and two displays at the same time.

This is a common anode 4-digit tube display module which uses the TM1637 driver chip; Only 2 connections are required to control the 4-digit 8-segment displays

Features of the module

• Display common anode for the four red LED
• Powered supply by 3.3V/5V
• Four common anode tube display module is driven by IC TM1637
• Can be used for Arduino devices, two signal lines can make the MCU control 4 8 digital tube. Digital tube 8 segment is adjustable

Parts Required

The TM1637 display module can be acquired for under $1

Name	Link
Pico	Raspberry Pi Pico Development Board
TM1637 module	TM1637 Red Digital Tube LED Module
Connecting cables	Aliexpress linkAmazon.com link Ebay link

Schematic/Connection

Black for GND
Red for V+
Blue for DIO
Yellow for CLK

This layout shows a connection to the module

rp2040 and tm1637

Code Examples

I used Thonny for development

The following is based on this library which you can copy to your Raspberry Pi Pico – max7219 library

scrolling message

Source code

from machine import Pin
import utime
import tm1637
 
tm = tm1637.TM1637(clk=Pin(1), dio=Pin(0))
 
tm.brightness(2)
 
while True:
    tm.scroll('Hello World') # 4 fps
    utime.sleep(1)
    tm.scroll('Hello World', 1000) # 1 fps
    utime.sleep(1)

Display some numbers

Source code

from machine import Pin
import utime
import tm1637
 
tm = tm1637.TM1637(clk=Pin(1), dio=Pin(0))
 
tm.brightness(2)
 
while True:
    # show "   1" (numbers right aligned)
    tm.number(1)
    utime.sleep(1)
    # show "  12"
    tm.number(12)
    utime.sleep(1)
    # show " 123"
    tm.number(123)
    utime.sleep(1)
    # show "1234"
    tm.number(1234)
    utime.sleep(1)

A counter

Source code

from machine import Pin
import utime
import tm1637
 
tm = tm1637.TM1637(clk=Pin(1), dio=Pin(0))
 
tm.brightness(2)
tm.show('    ')
 
number = 0
while number < 1000:
    number += 1
    tm.number(number)
    utime.sleep(0.01)

Usage example

Source code

from machine import Pin
import utime
import tm1637
 
tm = tm1637.TM1637(clk=Pin(1), dio=Pin(0))
 
tm.brightness(2)
tm.show('    ')
 
# all LEDS on "88:88"
tm.write([127, 255, 127, 127])
utime.sleep(1)
# all LEDS off
tm.write([0, 0, 0, 0])
utime.sleep(1)
# show "0123"
tm.write([63, 6, 91, 79])
utime.sleep(1)
# show "COOL"
tm.write([0b00111001, 0b00111111, 0b00111111, 0b00111000])
utime.sleep(1)
# show "HELP"
tm.show('help')
utime.sleep(1)
# display "dEAd", "bEEF"
tm.hex(0xdead)
tm.hex(0xbeef)
utime.sleep(1)
# show "12:59"
tm.numbers(12, 59)
utime.sleep(1)
# show "-123"
tm.number(-123)
utime.sleep(1)
# show temperature '24*C'
tm.temperature(24)

The following are available according to the documents

Methods

Get or set brightness.

brightness(val=None)

Write one or more segments at a given offset.

write(segments, pos=0)

Convert a single hex digit (0x00-0x0f) to a segment.

encode_digit(digit)

Convert a string to a list of segments.

encode_string(string)

Convert a single character to a segment.

encode_char(char)

Display a number in hexadecimal format 0000 through FFFF.

hex(val)

Display a number -999 through 9999, right aligned.

number(num)

Display 2 independent numbers on either side of the (optional) colon, with leading zeros.

numbers(num1, num2, colon=True)

Display a temperature -9 through 99 followed by degrees C.

temperature(num)

Show a string on the display. Shorthand for write(encode_string()). Limited to first 4 characters.

show(string, colon=False)

Display a string on the display, scrolling from the right to left, speed adjustable. String starts off-screen and scrolls until off-screen at 4 FPS by default.

scroll(string, delay=250)

Links

Based on this library

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