read-sd-sector.py

from machine import SD
import os

sd = SD()
sd.ioctl(1,0)

def pr(buf):
  l=len(buf)
  c=0
  while(c<l):
    print("%04x:" % c, end='')
    for i in range(16):
      print("%02x " % buf[c+i], end='')
    print("  ", end='')
    for i in range(16):
      b = buf[c+i]
      if b>0x20 and b<0x7f:
        print(chr(b), end='')
      else:
        print('.', end='')
    print()
    c += 16

buf=bytearray(512)
sd.readblocks(0xbb00,buf)

pr(buf)