Electronic – Problem with LED Matrix Test

led

I'm currently working on a project for school and am using a makeshift LED matrix from lilypad LEDs to sew onto a tapestry. Right now I'm just testing with one LED for now (see schematic on my arduino forum post here). I've run into a problem where the light is
1) very dim
2) not responding to my SHIFTOUT command. Regardless of whether the pin on the shift register is off or on, the led just shines really dimly. This is the code:

int clockSource =7;
int latchSource =6;
int dataSource =5;
int clockSink =12;
int latchSink =11;
int dataSink =13;

 setup(){
 pinMode(clockSource,OUTPUT);
 pinMode(latchSource,OUTPUT);
  pinMode(dataSource,OUTPUT);
    pinMode(clockSink,OUTPUT);
      pinMode(latchSink,OUTPUT);
        pinMode(dataSink,OUTPUT);
}
void loop(){
digitalWrite(latchSource,LOW);
digitalWrite(latchSink,LOW);

shiftOut(dataSink,clockSink,MSBFIRST,254);
shiftOut(dataSource,clockSource,MSBFIRST,4);

    digitalWrite(latchSource,HIGH);
digitalWrite(latchSink,HIGH);

}

For clarification, the wire I'm using is 9 ohms/foot conductive thread, and Lilypad protoboards for the shift registers, even though it doesn't show in the attached diagram.

Best Answer

Here's your circuit and shown in red are vital connections that you are missing: -

enter image description here

GND means ground and is an absolute must

Blue is the output enable pin and is also an absolute must

Green is also quite important - basically any unused inputs MUST be tied to Vcc or GND as appropriate for their functionality.

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