Freematics Forum

H/W - Freematics One

Is there a way to program the fuse and/or memory lock bits through the micro USB connection?

Thanks,
DB

I've tried the following things to program the lock bits:

1. Platform I/O Configuration
   I'm using Visual Studio Code...
   The platformio.ini file is as follows:
   ;start of file
   [env:uno]
   platform=atmelavr
   board=uno
   framework=arduino
   monitor_speed=115200
   upload_flags = -Ulock:w:0xFC:m
   lib_extra_dirs=../libraries
   
   [platformio]
   src_dir=.
   ;end of file
   but when uploading to the board, the procedure fails and says
   avrdude: verifying ...
   avrdude: verification error, first mismatch at byte 0x0000
   0x00 != 0xfc
   avrdude: verification error; content mismatch
2. AVRDUDE
   I tried the command:
   avrdude -u -c arduino -p m328p -P COM7 -b 115200 -U lock:r:-:h
   that command always returns 0x00
   I've also tried writing with AVRDUDE:
   avrdude -u -c arduino -p m328p -P COM7 -b 115200 -U lock:w:0xFC:m
   avrdude: Device signature = 0x1e950f (probably m328p)
   avrdude: reading input file "0xFC"
   avrdude: writing lock (1 bytes):
   avrdude: 1 bytes of lock written
   avrdude: verifying lock memory against 0xFC:
   avrdude: load data lock data from input file 0xFC:
   avrdude: input file 0xFC contains 1 bytes
   avrdude: reading on-chip lock data:
   avrdude: verifying ...
   avrdude: verification error, first mismatch at byte 0x0000
   0x00 != 0xfc
   avrdude: verification error; content mismatch
   
   avrdude done. Thank you.
3. Program During Runtime
   There's a lot of forums that claim you can program the lock bits by including the header file <avr/boot.h> and by calling
   boot_lock_bits_set_safe(0x03);

In the software I'm calling:
lbits = boot_lock_fuse_bits_get(GET_LOCK_BITS)
which always returns 0xFF
I'm also fairly confident that none of these attempts to lock the device are working because the command:
avrdude -c arduino -p m328p -P COM7 -b 115200 -U flash:r:"D:\download.hex":h
creates a file that has the same contents as the .hex that I'm uploading to the ECU.