ST7735 Graphic Error

[IsaNocNoc]

Hello, I am trying to graph a voltage divider of a potentiometer but I get an error that I cannot understand.
This is the code:

from machine import SPI,Pin,ADC
from ST7735 import TFT
from sysfont import sysfont
import time

# Configuración de pines SPI
spi = SPI(0, baudrate=20000000, polarity=0, phase=0, sck=Pin(2), mosi=Pin(3), miso=Pin(4))

# Configuración de pines de control de la pantalla
tft=TFT(spi,0,7,1)
tft.initr()  # O tft.initr() si es una pantalla "red tab"
tft.rgb(True)
# Rellenar la pantalla con un color de fondo
tft.fill(TFT.BLACK)
def plot_time(yp, x, y, t,var=[0.0,3.3], vpts=[25,16,25,55], hpts=[25,55,112,55]):
    tft.line((vpts[0],vpts[1]),(vpts[2],vpts[3]),TFT.GREEN)
    tft.line((hpts[0],hpts[1]),(hpts[2],hpts[3]),TFT.RED)
    tft.text((vpts[0]-25,hpts[1]-5),str(round(var[0],1)),TFT.WHITE,sysfont,1)
    tft.text((vpts[0]-25,vpts[1]),str(round(var[1],1)), TFT.WHITE,sysfont,1)
    
    y[1]=int((yp-var[0])/(var[1]-var[0])*(vpts[1]-hpts[1])+hpts[1])
    if t < hpts[2]-hpts[0]:
        x[1]=x[0]+1
    else:
        x[1]=hpts[2]
        
    tft.line((x[0],y[1]),(x[1],y[1]), TFT.BLUE)
    y[0]=y[1]
    x[0]=x[1]
    
    if t > hpts[2]-hpts[0]:
        tft.line((vpts[0],vpts[1]),(2,vpts[2]),TFT.WHITE)
        tft.line((vpts[0]-25,vpts[1]),(vpts[0],vpts[2]+5),TFT.YELLOW)
        tft.setvscroll(-1,0)
        tft.line((vpts[0],vpts[1]),(vpts[2],1),TFT.GREEN)
        tft.line((hpts[0], hpts[1]), (hpts[2], 1), TFT.RED)
        tft.text((vpts[0]-25,hpts[1]-5),str(round(var[0],1)),TFT.WHITE,sysfont,1)
        tft.text((vpts[0]-25,vpts[1]),str(round(var[1],1)), TFT.WHITE,sysfont,1)
    else:
        t+=1
        
    return t,x,y

if __name__=='__main__':
    
    FACTOR=5.0/(65535)
    
    pot = ADC(28)
    
    t=0
    y=[55,55]
    x=[25,25]
    
    while True:
        volts=pot.read_u16()*FACTOR
        t,x,y=plot_time(volts,t,x,y)
        tft.line((0,0),(120,15),TFT.NAVY)
        tft.text((0,0),"Volts: ",TFT.WHITE,sysfont,1)
        tft.text((52,0),str(round(volts,1)),TFT.WHITE,sysfont,1)
        time.sleep_ms(100)

The Error:

Traceback (most recent call last):
  File "<stdin>", line 56, in <module>
  File "<stdin>", line 22, in plot_time
TypeError: unsupported types for __lt__: 'list', 'int'

[karfas]

See these lines:

def plot_time(yp, x, y, t,var=[0.0,3.3], vpts=[25,16,25,55], hpts=[25,55,112,55]):
...
# in __main__
t,x,y=plot_time(volts,t,x,y)

So you are giving the t parameter in plot_time() main's y array.
Further down the exception tells you it can't compare apples to peaches (an array to an integer or something like that).