mcp3204-mp.py

class MCP3204:
    def __init__(self, spi, cs):
        self.spi = spi
        self.cs = cs

    def read(self, ch):
        cmd = 6 | (ch >> 2)
        par = (ch << 6) & 0xff
        send = bytearray([cmd, par, 0])
        recv = bytearray(3)
        self.cs.value(0)
        self.spi.write_readinto(send, recv)
        self.cs.value(1)
        return int.from_bytes(recv, 'big')

from machine import SPI, Pin
from time import sleep

spi=SPI(0)
cs=Pin(22, Pin.OUT)
adc=MCP3204(spi,cs)
while(True):
    print(adc.read(0))
    sleep(1)