Meowbit read and write Flash

rw_flash.py

from meowbit import screen
from meowbit import pyb

fl = pyb.Flash()

# Doc: 
#   1. https://docs.micropython.org/en/latest/library/pyb.Flash.html#pyb-flash
#   2. https://docs.micropython.org/en/latest/reference/filesystem.html#stm32-pyboard

# 4000th blocks to read and write, as Meowbit has 2MB flash size, 
# it has 1024 * 1024 * 2 / 512 = 4096 blocks
start = 4000 

bufr = bytearray(512) # Every block size is 512
fl.readblocks(start, bufr)

s = "" + str(bufr[0])

screen.text(s)

buf = bytearray(512)
buf[0] = bufr[0] + 1
if buf[0] > 255:
    buf[0] = 255
fl.writeblocks(start, buf)