Hi Joakim, Thanks for the quick reply. Thanks. (2012/07/31 14:20), Joakim Linde wrote: Hi Karel, You read/write the whole blob with CoreBluetooth. The CoreBluetooth framework will then break it down in smaller chunks for you automatically. Thanks, Joakim On Jul 30, 2012, at 9:50 PM, karel <karel@tandd.co.jp> wrote: I have been working from example code for a Bluetooth LE application on the iPhone4S and have reused the readValueForCharacteristic and writeValue:forCharacteristic for accessing attributes which will fit into one packet (i.e. length less than 20bytes or so). Are there any read/write functions available for accessing a subrange of large attributes, that is, how does one do Read/Write Blob with iOS (on the iPhone4S)? Thanks. Karel _______________________________________________ Do not post admin requests to the list. They will be ignored. Bluetooth-dev mailing list (Bluetooth-dev@lists.apple.com) Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/bluetooth-dev/joakim%40apple.com This email sent to joakim@apple.com _______________________________________________ Do not post admin requests to the list. They will be ignored. Bluetooth-dev mailing list (Bluetooth-dev@lists.apple.com) Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/bluetooth-dev/site_archiver%40lists.... This email sent to site_archiver@lists.apple.com I can understand the automation of a writeblob since the total length of the data is held within the NSData structure. But how can readValueForCharacteristic determine the length of the read, and how does it handle reading from an attribute who's length may not be fixed? P.S. If there is documentation detailing the above functionality, please post a link; as honestly, until the iPhone I am now working on, I have not used an Apple device since the Apple II s we had at high school.