MTU size change then infinite reboot

[Jake]

I'm using nRF52DK and SDK12.2.0. Trying to change MTU size.

When I modified app_nrf_uart example as below

#define NRF_BLE_MAX_MTU_SIZE            103 

Then infinite reboot at below

#if (NRF_SD_BLE_API_VERSION == 3)
    ble_enable_params.gatt_enable_params.att_mtu = NRF_BLE_MAX_MTU_SIZE;
#endif
    err_code = softdevice_enable(&ble_enable_params);

softdevice_enable returns 0x04

Please help me to change MTU size.

[minswho]

I realized that my serial monitor was connected to the other nrf chip that wasn't flashed with new ram start address yet.

I increased the RAM start address and corresponding size with r1 values from both central and peripheral sketch and it seems to be working fine.

But could you tell me what the maximum MTU size is for the current SDK? I'm getting contradicting information from various sources.

This is my current definition.

#define NRF_BLE_MAX_MTU_SIZE    103