writing to individual char field without having to send all other fields

[kuddy]

So right now i have one characteristic which is writable and it has 8 different fields within it. If I read it with nrf connect app i get 0B-00-0C-00-0D-00-0E-00-0F-00-10-00-00 which is fine. Say i want to write to it I and i send it a byte array of just FF instead of the full 13 bytes, it accepts it and my data is now FF-00-00-00-00-00-00-00-00-00-00-00-00.

Is it possible to modify only one field at a time, maybe with a different profile structure? If not is it the central's job to ensure it is sending the full characteristic (the full 13 bytes)? Is there any way to set up the peripheral to reject malformed characteristic data? Fixed length maybe?

I'm sure this was asked before but I didn't know what to search for.

thanks

[Petter Myhre]

So you write only 0xFF and want only byte 0 to change? How do you know byte 1-12 is 0x00? Do you read it?