Hi,

>          Solved the issue. Using the chainloading flag did the magic. Thanks
> Sylvain Munaut. For future references, this can work, if you bump into same
> error (I think even the cable in use can affect the transfer)
>
>> ./osmocon -p /dev/ttyUSB0 -m c123xor -c
>> ../../target/firmware/board/compal_exx/FIRMWARE.compalram.bin

Are you sure you used the compalram.bin ?  I seem to remember that
chainloading requires the .highram.bin version.

Cheers,

    Sylvain