CCS/LAUNCHXL-CC2640R2: BLE5 broadcaster and observer breaks the flahs-space-limit, only 5k for application?

Part Number: LAUNCHXL-CC2640R2

Tool/software: Code Composer Studio

Hi forum members,

I extend the ble5_simple_broadcaster with observer functionality. Therefore I add the #include <gap_scanner.h>. The compiler makes no error. But the linker dont find the lib / obj  of the GapScan_xyz functions. See screenshot.

Which linker file i have to add?

best regards

Bjoern

Hi Bjoern,

To fix this linker error, you will need to edit build_config.opt, found under TOOLS in the stack project. Under "BLE Host Build Configurations," comment out "-DHOST_CONFIG = BROADCASTER_CFG" and uncomment "-DHOST_CONFIG = CENTRAL_CFG + BROADCASTER_CFG"

Hi Jessica Heider,

thanks for reply.

After activate the "-DHOST_CONFIG=CENTRAL_CFG+BROADCASTER_CFG" in build_config.opt there are two more problems:

1) linker now dont find the GattServApp (see screenshot)

2) the size of my application drops out (with dbg 0-optimizations before central-role it was 80k) it explode to 134k (6k to less). Screenshot shows size with 117k full-size because I go back to full-size-optimizations level 4.

In my application there will be used only the GAP functionality (no GATT-Services are needed). If the device receive advert-data with the max 31byte-advert-field the application shall handle this about the GAP-Messages. The complete overhead is not neccessary, also the linked dataexchange (central+peripheral) will not used. Only broadcast-advertising and observer functionality will be required. I think there must be a lot of flash-space left to fill this with my application and not with not needed overhead.

Now my question: Are there possibilites to activate only broadcast / observer functionality without GATT and so on? Perhaps with other methods / functions?

sincere regards

Bjoern

Hi Bjoern,

We currently do not support broadcaster/observer multi-role. In order to fix those build errors, you will need to link gattservapp_util.c and sm_ecc.c (CC2640R2_SDK/source/ti/ble5stack/host) into your project. What is your application for? Are there specific BLE5 features that you are using in your project? If not, our BLE4.2 stack does not use as much flash memory. If BLE5 is a necessity, I would recommend considering our CC26x2 device that has more memory. Otherwise, we can try to find a way to reduce memory usage in your application.

Hi Bjoern,

We’re working on a response to this in detail.
In general flash size is limited on ble5 for cc2640r2

Merging threads together since this is relatively the same topic and same author.

As Sean pointed out, the flash size is inherently limited on CC2640R2 when using the BLE5 stack.

Have you looked at the CC2642 device? It features BLE5 and has much more flash availability. Typically we recommend people only use the CC2640R2 BLE5 stack when there is not a need for a ton of application code. Because the multi-role-ish type nature, it could be hard to develop your solution as you've pointed out with your code optimization setting comments.

Can you look into the CC2642? www.ti.com/.../CC2642R

Hi Jessica, hi Evan, hi Sean,
thanks for reply.

We will need BLE5 because long-range phy-coded-8. This is the first real long-range version whith the benefits of bluetooth (pyh: channel-hopping, business: bluetooth is sexy and sales). Our tests results are ranges of 30mtr in house with walls / doors / loss with safe transmission. The base is one of the best on market, that is the reason on ble5.

Now we have to look on the other devices you prefer, but there are no distributors in europe who stock the CC2642R and CC2652. So we done ti-register for samples.

One more question before I close this post: When will the devices CC2642R and CC2652R come to market (no preview / distributor with stock / mass production)?

best regards,
Bjoern