BLE Characteristic Read max data length

Former Member over 5 years ago

For BLE.requestRead I noticed the documentation says:

Support for long reads is not implemented.

But what is a long read? I am trying to understand how many bytes I can pass at one time, or is this called multiple times for large data?

Top Replies

jim_m_58 over 5 years ago in reply to Former Member +1 verified

Notify has the same limit if I recall. They only thing you can do is break up your data into small pieces.
jim_m_58 over 5 years ago in reply to Former Member +1

You could also use different characteristics for the different types of data. Say you have 6 values, use 6 different characteristics.

All Replies

0 jim_m_58 over 5 years ago

The current max is about 22 bytes of data for a read if I recall. Maybe a few more, but I'd have to hack together a test. It's not much so avoid things like a string.

0 Former Member over 5 years ago in reply to jim_m_58

I was hoping for a byte array. Is all communication like that,or is it possible with another way?

I was trying to avoid notify

0 jim_m_58 over 5 years ago in reply to Former Member

Notify has the same limit if I recall. They only thing you can do is break up your data into small pieces.

0 Former Member over 5 years ago in reply to jim_m_58

Oh, thats perfect, and indicate when im ready for more?

I havent tried using indicators yet

0 jim_m_58 over 5 years ago in reply to Former Member

You could also use different characteristics for the different types of data. Say you have 6 values, use 6 different characteristics.

0 Former Member over 5 years ago in reply to jim_m_58

don't suppose you know how the companion app is able to send large data over? that would be interesting if I could use something like that

0 jim_m_58 over 5 years ago in reply to Former Member

It's something you'd need to handle yourself between CIQ and the companion app.