Need help with timer project

i'm learning , i'm having trouble code , getting error message (exit status 1
lvalue required left operand of assignment). i'm trying create system when start_button pushed, turns on greenled amount of time goes , turns off greenled , turns on yellowled. redled. kind of stop light can't use delay because have 2 more buttons need monitor. i'm not going add other buttons until part of code working. appreciated.

code: [select]

const int ledpin =  3;      // number of led pin

// variables change:
int ledstate = low;             // ledstate used set led
long previousmillis = 0;        // store last time led updated
boolean start_state = false;    // start button status set false until button pressed
// following variables long because time, measured in miliseconds,
// become bigger number can stored in int.
long interval_1 = 300;           // interval between green , yellow led}
long interval_2 = 300;           // inteval between yellow , red led)

#define greenled 2
#define yellowled 3
#define redled 4
#define start_button 8
#define emergency_button 9
//#define open_button 10   ***this switch unused****


void setup() {
 
  // set digital pin output:
  pinmode(greenled, output);
  pinmode(yellowled, output);
  pinmode(redled, output);
  pinmode(start_button, input);//input start button
  pinmode(emergency_button, input);//input emergency button

 
}

void loop()
{
  // check see if it's time blink led; is, if
  // difference between current time , last time blinked
  // led bigger interval @ want
  // blink led.
 digitalwrite(redled = low)
  unsigned long currentmillis = millis();
{
  if (digitalread(start_button) == high)//if start button pressed
    {
    start_state = true;
    if (start_state == high);
    digitalwrite(greenled = high);
   
    }

  if(currentmillis - previousmillis > interval_1) {
    // save last time blinked led
    previousmillis = currentmillis;   
{
    digitalwrite(greenled = low);
    digitalwrite(yellowled = high);
}

   if(currentmillis - previousmillis > interval_2) {
    // save last time blinked led
    previousmillis = currentmillis;
 
    digitalwrite(yellowled = low);
    digitalwrite(redled = high);
   
 
  }
}

quote from: devilstang on jun 25, 2016, 04:27 pm

code: [select]

   digitalwrite(greenled = high);

should

code: [select]

digitalwrite(greenled, high);
and other digitalwrite() calls need same change.
please read https://www.arduino.cc/en/reference/digitalwrite

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