Display a digital clock using a Pico Scroll Pack

In this article we will display a digital clock using a Pico Scroll Pack

Getting started

The labels on the underside of Pico Scroll Pack will show you which way round to plug it into your Pico – just match up the USB port with the markings on the board.

The easiest way to get started is by downloading and copying the custom MicroPython uf2 to your Pico, it includes all the libraries you’ll need to use our add-ons.

https://github.com/pimoroni/pimoroni-pico/releases/latest/

To be able to copy this file on to your Pico, you’ll need to put it into bootloader mode. To do this, hold down the BOOTSEL button whilst plugging the USB cable into your computer – it should now show up as a drive called RPI-RP2. Here’s what it looks like in Windows:

Copy the downloaded .uf2 file across to this new drive. Your Pico will now reboot

Code examples

If you see the following message

WARNING: Could not sync device’s clock: can’t import name RTC
WARNING: Could not validate time: can’t import name RTC

Make sure if you are using Thonny IDE then in the Interpreter options select the Micropython(Raspberry Pi Pico) and reloading the shell with the stop icon, those two messages referring to the RTC error will go away.

Otherwise you will see that the time on the scroll pack will not be correct

Here is an example

Source code

import math
import utime
import picoscroll as scroll
from machine import Pin
 
scroll.init()
 
secupdated = False
led = Pin(25,Pin.OUT)
 
# Initial time, from RTC if set via the shell, or 12:30:01 otherwise (if RTC is unset, epoch is 1/1/21 00:00:01)
if utime.localtime()[0] == 2021 and utime.localtime()[1] == 1 and utime.localtime()[2] == 1:
    hours = 12
    minutes = 30
    seconds = 1
    sync = False
    led.low()
else:
    hours = utime.localtime()[3]
    minutes = utime.localtime()[4]
    seconds = utime.localtime()[5]
    sync = True
    led.high()
 
# LED Brightness (0-255)
brightness = 50
 
# Character pixel maps (3w x 5h font)
zero = [0,1,1,1,0],[1,0,0,0,1],[0,1,1,1,0]
one = [0,1,0,0,1],[1,1,1,1,1],[0,0,0,0,1]
two = [1,0,0,1,1],[1,0,1,0,1],[0,1,0,0,1]
three = [1,0,1,0,1],[1,0,1,0,1],[0,1,0,1,0]
four = [0,1,1,1,0],[1,0,0,1,0],[0,0,1,1,1]
five = [1,1,1,0,1],[1,0,1,0,1],[1,0,0,1,0]
six = [0,1,1,1,0],[1,0,1,0,1],[0,0,0,1,0]
seven = [1,0,0,1,1],[1,0,1,0,0],[1,1,0,0,0]
eight = [0,1,0,1,0],[1,0,1,0,1],[0,1,0,1,0]
nine = [0,1,0,0,0],[1,0,1,0,1],[0,1,1,1,0]
error = [1,1,1,1,1],[1,0,1,0,1],[1,0,1,0,1]
charlist = [zero,one,two,three,four,five,six,seven,eight,nine]
 
# Draw characters using above pixel maps, left to right, top to bottom
def draw_digit(x,y,map):
    global brightness
 
    scroll.set_pixel(x,y,map[0][0]*brightness)
    scroll.set_pixel(x+1,y,map[1][0]*brightness)
    scroll.set_pixel(x+2,y,map[2][0]*brightness)
 
    scroll.set_pixel(x,y+1,map[0][1]*brightness)
    scroll.set_pixel(x+1,y+1,map[1][1]*brightness)
    scroll.set_pixel(x+2,y+1,map[2][1]*brightness)
 
    scroll.set_pixel(x,y+2,map[0][2]*brightness)
    scroll.set_pixel(x+1,y+2,map[1][2]*brightness)
    scroll.set_pixel(x+2,y+2,map[2][2]*brightness)
 
    scroll.set_pixel(x,y+3,map[0][3]*brightness)
    scroll.set_pixel(x+1,y+3,map[1][3]*brightness)
    scroll.set_pixel(x+2,y+3,map[2][3]*brightness)
 
    scroll.set_pixel(x,y+4,map[0][4]*brightness)
    scroll.set_pixel(x+1,y+4,map[1][4]*brightness)
    scroll.set_pixel(x+2,y+4,map[2][4]*brightness)
    return
 
# Process clock characters
def character(x,y,char):
    global charlist
    if char >= 0 and char <=9:
        draw_digit(x,y,charlist[char])
        return
    else:
        draw_digit(x,y,error)
        return
 
# Act on button presses
def buttonhandler():
    global hours, minutes, brightness, led
 
    if scroll.is_pressed(scroll.BUTTON_A):
        led.low()
        if scroll.is_pressed(scroll.BUTTON_X):
            if brightness <= 245 and brightness >= 10:
                brightness += 10
            elif brightness < 255 or brightness < 10:
                brightness += 1
        else:
            hours += 1
        return
 
    if scroll.is_pressed(scroll.BUTTON_B):
        led.low()
        if scroll.is_pressed(scroll.BUTTON_Y):
            if brightness >= 11 and brightness <= 250:
                brightness -= 10
            elif brightness > 3 or brightness > 250 :
                brightness -= 1
        else:
            hours -= 1
            if hours < 0:
                hours = 23
        return
 
 
    if scroll.is_pressed(scroll.BUTTON_X):
        led.low()
        minutes += 1
        return
 
    if scroll.is_pressed(scroll.BUTTON_Y):
        led.low()
        minutes -= 1
        if minutes < 0:
            minutes = 59
        return
 
def draw_clock(hrs,mins,secs):
    global brightness
    scroll.clear()
 
    character(0,0,hrs//10) # hour tens (0-2)
    character(4,0,hrs%10) # hour units (0-9)
    character(10,0,mins//10) # minute tens (0-5)
    character(14,0,mins%10) # minute units (0-9)
 
    if(secs % 2 != 0): # draw colon between hours and minutes on odd seconds
        scroll.set_pixel(8,1,brightness)
        scroll.set_pixel(8,3,brightness)
 
    # seconds pixel bar across the bottom - borrowed from the scrollphathd clock example
    seconds_progress = 15 * ((secs % 60) / 59.0)
    for y in range(15):
        current_pixel = min(seconds_progress, 1)
        scroll.set_pixel(y + 1, 6, int(current_pixel * brightness))
        seconds_progress -= 1
        if seconds_progress <= 0:
            break
 
    scroll.update()
 
# Main clock loop
while True:
    utime.sleep(0.5)
    seconds = utime.localtime()[5]
 
    buttonhandler()
 
    if seconds == 0 and secupdated == False:
        minutes += 1
        secupdated = True
 
    if seconds == 1 and secupdated == True:
        secupdated = False
 
    if minutes > 59:
        hours += 1
        minutes = 0
 
    if hours > 23:
        hours = 0
 
    draw_clock(hours,minutes,seconds)

Products

Name	Link
Pico	Raspberry Pi Pico Development Board A Low-Cost High-Performance Microcontroller Board RP2040 Cortex-M0+ Dual-Core ARM Processor
Pico Scroll Pack UK	Pico Scroll Pack