https://devzone.nordicsemi.com/f/nordic-q-a/87417/is-it-possible-to-have-a-zero-length-characteristic-readWe&#39;re using the read authentication trigger to detect when a characteristic is being read, so we can update the value before a read. Is it possible to have a read with zero length? This is the data handler for the service, and I did confirm that iten-USTelligent Community 13Wed, 04 May 2022 11:42:26 GMThttps://devzone.nordicsemi.com/thread/366206?ContentTypeID=1Wed, 04 May 2022 11:42:26 GMT137ad170-7792-4731-bb38-c0d22fbe4515:acb08ccc-7384-4125-8296-db033f070071CurtisHx2<p>Figured out what we doing wrong.&nbsp; We were giving the characteristic an initial length of 1 and there was also a problem where the value (and new length) was not getting updated correctly in the code base.&nbsp;</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/365681?ContentTypeID=1Mon, 02 May 2022 06:32:19 GMT137ad170-7792-4731-bb38-c0d22fbe4515:39d01738-da82-4a00-9270-a0db5198396bAmanda Hsieh<p>Hi,&nbsp;</p> <p>When you init the characteristic with characteristic_add(), please try to set this:</p> <p>add_char_params.is_var_len = true;</p> <p>Regards,<br />Amanda</p><div style="clear:both;"></div>