from machine import Pin, I2C
import time
import ssd1306

# OLED setup
oled = ssd1306.SSD1306_I2C(128, 64, I2C(0, scl=Pin(1), sda=Pin(0)))

# LED setup
red = Pin(15, Pin.OUT)
green = Pin(14, Pin.OUT)

def show(msg, t):
    oled.fill(0)
    oled.text(msg, 35, 20)
    oled.text("TIME: {}".format(t), 25, 40)
    oled.show()

def light(rv, gv, start, end, step, msg):
    red.value(rv)
    green.value(gv)
    for i in range(start, end-1, step):   # include 0
        show(msg, i)
        time.sleep(1)

while True:
    light(1, 0, 30, 0, -1, "STOP")   # Red
    light(1, 1, 5, 0, -1, "READY")   # Red+Green
    light(0, 1, 30, 0, -1, "GO")     # Green
    light(1, 1, 5, 0, -1, "READY")   # Red+Green