Increase max connections on cc2650

Wei Lu

Expert 1900 points

Other Parts Discussed in Thread: CC2640

Hi,

I'd like to make BLE central to connect multiple peripherals, maybe up to 20,

but due to internal flash and RAM, it can only reach 8 connections at the same time.

What if I use external flash to save connection information? Can it reach to 20?

Thanks,

Wei

over 9 years ago

0 Christin Lee over 9 years ago

TI__Guru 56345 points

It's doable, however, you will have to change the low level files (nvocop.c/nvocop.h). There files locates here: C:\ti\simplelink\ble_sdk_2_02_00_31\src\components\services\src\nv\cc26xx

0 Wei Lu over 9 years ago in reply to Christin Lee

Expert 1900 points

Hi Christin,

Thanks for your reply,
and may I ask you what parameters should I modify in these files? SNV_FIRST_PAGE? RAM_BUFFER_ADDRESS?

Thanks a lot,
Wei

0 Christin Lee over 9 years ago in reply to Wei Lu

TI__Guru 56345 points

You have to modify everything since the current implementation uses register access.

If you take a look at the NVOCOP_initNV function in nvocop.c, you will see that if you are using OSAL_SNV, then you will see all the functions are eventually just HWREG read and write.

For your case, you will have to create serial communication(ex : SPI) in NVOCOP_initNV and then customize the osal_snv_read/osal_snv_write to write to external flash

0 Wei Lu over 9 years ago in reply to Christin Lee

Expert 1900 points

Hi,

Thanks for your reply and here are some question.
1. So I should pre-define OSAL_SNV=1 to call nvocop.c in the stack? But, according to cc2640 software guide, SNV data will loss after power off. I don't want it happen.

2. The information I should store into external flash are bonding info?

3. Can I modify osal_snv.c to do the same thing?

Wei

0 Christin Lee over 9 years ago in reply to Wei Lu

TI__Guru 56345 points

Just to be sure we are talking about the same thing, I am using BLE stack 2.2. as reference for this discussion.
1. Yes, you need to define OSAL_SNV =1 in order to use bondmgr. SNV data will not lose after power off. Where did you find the statement regarding SNV data will lose after power off?
2. yes. But the bondmgr will handle this for you.
3. You need to modify all the related files which include as stated nvocop.c and osal_snv.c

0 Wei Lu over 9 years ago in reply to Christin Lee

Expert 1900 points

Hi,

In SWRU393 cc2640 software guide, 3.10.4 Using Simple NV (SNV),

"One flash sector is allocated to SNV. Bonding info is stored in NV. Flash compaction uses Flash cache RAM for intermediate storage, thus a power-loss during compaction will result in SNV data loss."

thanks I will try it.

Wei

0 Christin Lee over 9 years ago in reply to Wei Lu

TI__Guru 56345 points

The above sentence means only a power loss during flash compaction will cause SNV data loss. If the device operates at normal condition during bonding, then a Pin reset or power loss will not cause data loss in SNV

0 Wei Lu over 9 years ago in reply to Christin Lee

Expert 1900 points

Hi,

Can I just use bsp_spi which is applied for OAD in stack?
I tried to apply ext_flash.c to replace hal_flash.wrapper.c.

Wei

0 Christin Lee over 9 years ago in reply to Wei Lu

TI__Guru 56345 points

I am not following what you are going to do now. I thought you want to store bond info in external flash. Then the files you need to modify should be nvocop.c and osal_snv.c as starting point.

You can always refer to bsp_spi files for making connection to external flash, but this does not mean that your bond info will be stored in external flash until you modify those files I mentioned.

0 Wei Lu over 9 years ago in reply to Christin Lee

Expert 1900 points

Yes, that's what I was talking about, thank you!

Wei

0 Wei Lu over 9 years ago in reply to Christin Lee

Expert 1900 points

Hi,

After I add ext_flash.c/.h(used to control external flash) in stack,

there's an error happened,

and memory boundary define are

How can I do to fix the problem?

0 Wei Lu over 9 years ago in reply to Christin Lee

Expert 1900 points

Hi Christin,

Can you please answer my question?

0 Christin Lee over 9 years ago in reply to Wei Lu

TI__Guru 56345 points

Can you try to delete all the LCD print function from multirole project? You are running out of space. There is not much we can do about it

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Increase max connections on cc2650