rem: avr_txrx(fd, 0x28);
add: cmd[0] = 0x28;
context: unsigned char avr_read_byte ( int fd, unsigned short addr, int memtype ){  unsigned char r;  switch (memtype) {    case AVR_FLASH_LO:       avr_txrx(fd, 0x20);       break;    case AVR_FLASH_HI:       avr_txrx(fd, 0x28);       break;    case AVR_EEPROM:       avr_txrx(fd, 0xa0);       addr &= 0x7f;      break;    default:      fprintf(stderr, "%s: avr_read_byte(); internal error: invalid memtype=%d\n",              progname, memtype);      exit(1);      break;  }  avr_txrx(fd, addr >> 8);     /* high order bits of address       */  avr_txrx(fd, addr & 0x0ff);  /* low order bits of address        */  r = avr_txrx(fd, 0);         /* don't care                       */  return r;}