CC2640R2F: Service characteristic limit

Niklas Lange

Part Number: CC2640R2F
Other Parts Discussed in Thread: CC2640,

Hi,

I try to migrate from cc2640 (Stack 2.2.1) to cc2640r2f(Stack 1.40) using the porting guide: http://dev.ti.com/tirex/content/simplelink_cc2640r2_sdk_1_30_00_25/docs/blestack/ble_sw_dev_guide/html/cc2640/ble-sdg/porting-to-newer-stack-versions.html

My code is based on the simple peripheral example codes for both.

The code worked on the cc2640 processor without any problems but when I add custom characteristics, 26 in total with authentication required, it doesn't work. On iOS, using LightBlue App, it says it's connected but no data shows up and no pairing popup. On Android I get a pairing question and the unit is bonded after connection but no data is shown. The data is shown when I disconnect and reconnect to the unit.

If I lower the number of characteristics to 18 it works on both platforms.

So is there a limit to how many characteristics can be used with the cc2640r2f processor?

Best Regards

over 8 years ago

0 JXS over 8 years ago

TI__Guru** 105180 points

Hello Niklas,

We do not have a published service limit although the actual size will be based on how much RAM you have available. Can you check the heap memory usage when you encounter this condition?

Best wishes

0 Niklas Lange over 8 years ago in reply to JXS

Prodigy 200 points

Hello JXS,

When I go up from 18 characteristics to 20 I get the following data using HEAPMGR_METRICS. I also have auto heap size on.

The data is taken after a connection with a device has been made.

	18	20
HeapMgr_Size	4944	4832
heapmgrBlkMax	96	100
heapmgrBlkCnt	92	100
heapmgrBlkFree	26	40
heapmgrMemAlo	3132	2760
heapmgrMemMax	4808	4768
heapmgrMemUb	not found	not found
heapmgrMemFail	0	2

0 Niklas Lange over 8 years ago in reply to Niklas Lange

Prodigy 200 points

When adding CACHE_AS_RAM as a predefine I can add all 26 characteristics with authentication that I need. It works as before on iOS but on Android I still have the problem where I get a pairing question and the unit is bonded after connection but no data is shown. The data is shown when I disconnect and reconnect to the unit.

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CC2640R2F: Service characteristic limit