Display serial incoming data on tkinter scrollbar - python-3.x

Question

I downloaded a small arduino program in order for it to produce serial data.
My goal (first iteration) is to create an application that will replace the arduino IDE serial - since i only want to read serial data.
This is how the data looks like on the arduino IDE serial interface.
This is my code so far:
import tkinter as tk
import tkinter.ttk as ttk
import serial.tools.list_ports
from tkinter import scrolledtext
#new stuff
import time
import serial
import threading
import continuous_threading
#to be used on our canvas
HEIGHT = 700
WIDTH = 800
#hardcoded baud rate
baudRate = 9600
#Serial Stuff-----------------------------------------
ser = serial.Serial('COM16', baudRate)
val1 = 0
index = []
def readSerial():
global val1
ser_bytes = ser.readline()
ser_bytes = ser_bytes.decode("utf-8")
val1 = ser_bytes
index.append(val1)
disp = tk.Label(frame2, text=index[0])
disp.config(font=("TkDefaultFont", 8))
disp.place(relx = 0.1, rely=0.3, relwidth=0.3, relheight=0.5)
t1 = continuous_threading.PeriodicThread(0.5, readSerial)
# --- main ---
root = tk.Tk() #here we create our tkinter window
root.title("Sensor Interface")
#we use canvas as a placeholder, to get our initial screen size (we have defined HEIGHT and WIDTH)
canvas = tk.Canvas(root, height=HEIGHT, width=WIDTH)
canvas.pack()
# --- frame 2 ---
frame2 = tk.Frame(root, bg='#80c1ff') #remove color later
frame2.place(relx=0, rely=0.1, relheight=1, relwidth=1, anchor='nw')
# make a scrollbar
scrollbar = scrolledtext.ScrolledText(frame2)
scrollbar.place(relx=0, rely=0, relheight=1, relwidth=1, anchor='nw')
# --- frame 2 ---
t1.start()
root.mainloop() #here we run our app
I have a frame2 which is a scrollText that i want my data to appear (i also have another frame above it, that i removed it here so that i don't confuse people with unnecessary code).
Ideally i would like the data to appear like in the arduino IDE, with autoscroll - but first i have to walk before i can run.
All the serial "action" happens in the portion i have marked with comments called 'Serial stuff'.
Is my placement code correct?
disp = tk.Label(frame2, text=index[0])
disp.config(font=("TkDefaultFont", 8))
disp.place(relx = 0.1, rely=0.3, relwidth=0.3, relheight=0.5)
I want each line to be placed in a new line in the textbox, like my first picture
EDIT: I followed scotty3685's advice (Thanks a lot sir!) but look at what i get now at my tkinter frame:
If you compare with the first picture, it's close but it's not really there.

Answer 1

The way to insert text into a ScrolledText widget is as follows
s.insert("end","some_text that I want to insert")
s is the name of the scrolledtext widget (in your case this is
called scrollbar confusingly)
The first argument to insert "end"
tells the scrolled text widget to place the new text at the end of
the current text in the textbox.
and the second argument to insert is
the text you want to insert (in your case, val1).