74hc595 with four 7 Segment LEDs HDSP-5723

Hello friends,

thank you for you suggestions.

console.log("start");
//595 Pinput:
/*
 1 = 2
 2 = 3
 3 = 4
 4 = 5
 5 = 6
 6 = 7
 7 = 8 = Decimal Point/ DP
 8 = GND
 9 = carryover, to Next 595's SER/Pin 14

10 = SCL/CLR Rest, not used, flushing 32bit each time.
11 = Clock/SRCLK/SRCK, SPI1 SCK, Pin B3
12 = RCK/RCLK/LATCH/, SPI SS,Pin B6 via 10KOhm to Ground = Data Out
13 = Output Enable, GND
14 = Data/SER/SIN, SPI1 MOSI, Pin B5
15 = 1
16 = VCC 3,3V 330Ohm
*/

//SS Pin = B6

var sport  = 0b00000001;
var one    = 48;   // "00110000";
var two    = 91;   // "01011001";
var three  = 121;  // "01111001";
var four   = 116;  // "01110100";
var five   = 109;  // "01101101";
var six    = 111;  // "01101111";
var seven  = 56;   // "00111000";
var eight  = 127;  // "01111111";
var nine   = 125;  // "01111101";
var zero   = 63;   // "00111111";

var z = [zero,one,two,three,four,five,six,seven,eight,nine];

digitalWrite([B6,B7],0);         // SS Pin to 0
digitalWrite([B7],1);


SPI1.setup({ mosi:B5, sck:B3, baud:100000, order:'msb' }); //SPI Setup

var out = 0; // current Segment
var i   = 0; // Value to Display

var i1=0, i2=0, i3=0, i4=0;


setInterval(function(){
  i++;
  if (i>999)i=0;

  if (i>999){
    i1 = Math.floor(i/1000);
  } else {
    i1 = 0;
  }

  if (i>99){
    i2 = Math.floor(i/100) % 10;
  } else {
    i2 = 0;
  }

  if (i>9){
    i3 = Math.floor(i/10) % 10;
  } else {
    i3 = 0;
  }

  i4 = i % 10;

  //SPI1.write(buf_off,B6); //flush only needed when not writing to all four segements
  SPI1.write([ z[i4], z[i3],z[i2],z[i1] ],B6);
  //SPI1.write([ sport, sport, sport ], B6); //to debug a segement 

},100);

I have chained three additional 74HC595 s. The problem with that solution is, that i have no clue how to bring all this wires to a PCB breadboard.

I think i will have to do it the multiplexing way to avoid all this new cables.

2 Attachments

• 20151115_1039041.mp4
•