How to increase the MTU size in NRF52833?

[lara]

I have tried the below in proj.conf.iam using NRF52833 DK in VS CODE(NRF SDK Connect extension.Iam trying to receive data through gatt protocol,but it is not receiving more than 20 bytes.

toolchain version 2.8

also my build log showing ...

Memory region         Used Size  Region Size  %age Used
           FLASH:      203344 B       248 KB     80.07%
             RAM:       29188 B        32 KB     89.07%
        IDT_LIST:          0 GB        32 KB      0.00%

according to datasheet..512 KB Flash + 128 KB RAM for NRF52833DK.but the build log showing only 32kB of RAM,248kB of Flash.why?

CONFIG_BT_USER_DATA_LEN_UPDATE=y

CONFIG_BT_L2CAP_TX_MTU=247

CONFIG_BT_BUF_ACL_TX_SIZE=251

CONFIG_BT_BUF_ACL_RX_SIZE=251

[Simonr]

Try pressing the INFO tab on your phone and set it to VERBOSE or DEBUG to get more logging information, as the INFO only provides the most basic of information.

Best regards,

Simon

[lara]

i tried in 3 different phones but it still the same size

[Simonr]

Are you able to upload the verbose/debug log from the phone here so we can review it? 

Did you try increasing some of the stack sizes in your configs on your end? Specifically the ones below:

CONFIG_BT_RX_STACK_SIZE=1024

CONFIG_BT_HCI_TX_STACK_SIZE_WITH_PROMPT=y

CONFIG_BT_HCI_TX_STACK_SIZE=640

CONFIG_MAIN_STACK_SIZE=1024

Best regards,

Simon

[lara]

Connected
MTU exchange successfulNew MTU: 244 bytes

..........now its changed to 244 bytes,thank you simon for the kind support...

can i use the same config with nrf52840 dongle?

[Simonr]

What was the change necessary to achieve the MTU size you required? THe nRF52840 Dongle should work as long as you set the correct board file for it. The configs should work the same.

Best regards,

Simon

[lara]

yes simon it works for both nrf52833 and 52840 dongle aswell.it helped me like a heaven..haha..Thank you for ur kind response.