SPI Display Array Board – Clock

The main idea of this project was to make a customizable clock, a clock that would have the option to change its appearance very easily, The first option was to make it with RGB LEDs and change the color at will, maybe to have the ability to change the color according to the time of the day or with the ambient temperature, but what is more customizable than a display by itself, nowadays we can find very nice IPS Displays that are very cheap.

Maybe the hardest step of this project was the clock creation, making the graphics for each clock was really challenging as I wanted to look very similar to the real ones, like the Flip Clock, the seven-segment Display clock, the LED matrix clock.

Flip Clock
LED Matrix Clock
7-Segments Display Clock
Blue VFD Clock
Ink Clock
Wood Clock

These are only a few clocks that I have created, but it will be awesome to see other designs and that is why I’m sharing the design files of this project, I think it would be awesome to see how a project can evolve in the maker community.

I have also designed a 3D printed enclosure or in this case a frame. It consists of only 3 parts that glued together to make a single clock piece.

3D Printed clock bracket

The PCB is intended to be compatible with any Microcontroller or SBC like the Raspberry as it only needs some GPIOs and an SPI Port. This makes the PCB compatible with a simple microcontroller as an Arduino to other more advanced microcontrollers. We could say this board is a breakout board for the arrangement of six displays and 4 buttons.

SPI Display Array Board CAD

Testing the clock designs

Before writing the clock firmware I decided to test all the designs that I have already created on the computer, so using the Raspberry Pi Pico I have written a simple program that allows me to set an image for each display in order to simulate how the clock would look like.

The code for this simple task consists of the initialization of the displays and just sensing the raw data of each image to the corresponding display.

#include "pico/stdlib.h"
#include "hardware/gpio.h"
#include "hardware/pio.h"
#include "ST7735.h"

#include "clockDigital.h"
#include "clockFlip.h"
#include "clockMatrix.h"
#include "clockVFD.h"
#include "clockInk.h"
#include "clockWood.h"

#define ONBOARD_LED 25
 
int main(){
    stdio_init_all();

    PIO pio = pio0;
    uint sm = 0;
    uint offset = pio_add_program(pio, &SPILCD_program);
    lcdPIOInit(pio, sm, offset, PIN_SDI, PIN_SCK, SERIAL_CLK_DIV);


    gpio_init(ONBOARD_LED);
    gpio_set_dir(ONBOARD_LED, GPIO_OUT);

    gpio_init(PIN_CS1);
    gpio_init(PIN_CS2);
    gpio_init(PIN_CS3);
    gpio_init(PIN_CS4);
    gpio_init(PIN_CS5);
    gpio_init(PIN_CS6);
    gpio_init(PIN_DC);
    gpio_init(PIN_RST);
    gpio_init(PIN_BLK);
    
    gpio_set_dir(PIN_CS1, GPIO_OUT);
    gpio_set_dir(PIN_CS2, GPIO_OUT);
    gpio_set_dir(PIN_CS3, GPIO_OUT);
    gpio_set_dir(PIN_CS4, GPIO_OUT);
    gpio_set_dir(PIN_CS5, GPIO_OUT);
    gpio_set_dir(PIN_CS6, GPIO_OUT);
    gpio_set_dir(PIN_DC, GPIO_OUT);
    gpio_set_dir(PIN_RST, GPIO_OUT);
    gpio_set_dir(PIN_BLK, GPIO_OUT);

    gpio_put(ONBOARD_LED, 1);
    gpio_put(PIN_CS1, 0);
    gpio_put(PIN_CS2, 0);
    gpio_put(PIN_CS3, 0);
    gpio_put(PIN_CS4, 0);
    gpio_put(PIN_CS5, 0);
    gpio_put(PIN_CS6, 0);
    gpio_put(PIN_RST, 1);
    lcdInit(pio, sm, st7735_initSeq);
    gpio_put(PIN_BLK, 1);

    lcdStartPx(pio,sm);

    for (int i = 0; i < 160*80*2; i++){
       lcdPut(pio, sm, one_Flip[i]);
    }

    gpio_put(PIN_CS1, 1);
    for (int i = 0; i < 160*80*2; i++){
       lcdPut(pio, sm, two_Matrix[i]);
    }

    gpio_put(PIN_CS2, 1);
    for (int i = 0; i < 160*80*2; i++){
       lcdPut(pio, sm, three_Digital[i]);
    }

    gpio_put(PIN_CS3, 1);
    for (int i = 0; i < 160*80*2; i++){
       lcdPut(pio, sm, four_VFD[i]);
    }

    gpio_put(PIN_CS4, 1);
    for (int i = 0; i < 160*80*2; i++){
       lcdPut(pio, sm, five_Ink[i]);
    }

    gpio_put(PIN_CS5, 1);
    for (int i = 0; i < 160*80*2; i++){
       lcdPut(pio, sm, six_Wood[i]);
    }
}

For the SPI Display Array clock Firmware go to the Part2 of this project.


image/svg+xmlOpen Source Licenses HardwareSoftwareDocumentationCERN-OHL-P-2.0GPL-3.0-or-laterCC-BY-4.0


Visit my Tindie Store for the assembled board.

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