Problems with nrf Connect SDK App(BLE) and RTT Viewer

[Tal.]

Hello,

hello, when I connect a BLE Application with the RTT Viewer, my device does not appear in the nrf Connect APP. I need to disconnect the RTT Viewer so that the device appears in the app and I can connect to it. 

Shouldn't it be able to connect if it is also connected to the RTT Viewer at the same time? In the following you can see my prj.conf file:

#RTT-UART
CONFIG_SERIAL=y
CONFIG_USE_SEGGER_RTT=y
CONFIG_CONSOLE=y
#CONFIG_UART_CONSOLE=y


# CONFIG_USE_SEGGER_RTT=y
# CONFIG_CONSOLE=y
CONFIG_RTT_CONSOLE=y
# CONFIG_UART_CONSOLE=n


#NFCT Pins as GPIO
CONFIG_NFCT_PINS_AS_GPIOS=y

#Logging
CONFIG_LOG=y

#RTC
CONFIG_RTC=n

# Sensor
CONFIG_SENSOR=y

# Enable MPU
CONFIG_ARM_MPU=y

#GPIO
CONFIG_GPIO=y

# Button and LED library   
#CONFIG_DK_LIBRARY=y

# Bluetooth LE
CONFIG_BT=y

# Include the Peripheral Role support
CONFIG_BT_PERIPHERAL=y

#Change the Bluetooth LE device name to Nordic_Peripheral
CONFIG_BT_DEVICE_NAME="Nordic_HMI"

# Increase stack size for the main thread and System Workqueue 
CONFIG_SYSTEM_WORKQUEUE_STACK_SIZE=2048
CONFIG_MAIN_STACK_SIZE=2048

#BAS Service
#CONFIG_BT_BAS=n

#ADC
CONFIG_ADC=y

[KWolfe81]

I am observing a similar issue.  My device/board/design works perfectly fine until I "Connect" via the J-Link RTT Viewer.  As soon as I do, my BLE connection drops (same reason: 8).  Disconnecting the viewer, and my devices connect again perfectly.  Something about being connected with the Viewer is hosing things up.

[dejans]

Hi KWolfe81 ,

Is this behavior something that you can consistently reproduce?

Best regards,
Dejan

[KWolfe81]

Yes it is.  Note: I have an open (private) ticket for this issue.  It's 100% replicable on my custom board with my application or sample BLE applications, but 0% reproducible on a development board.

[dejans]

Hi,

Thank you for additional information.

If have an open private ticket for the same issue, I would suggest that you continue communication in the private ticket.

Best regards,
Dejan

[KWolfe81]

Following up - our decoupling cap placement was incorrect.  We had a 1uF cap on DEC6 (E24 whereas it should have been DEC4 (B5).  Moving it resolved the RTT/BLE connection issues.

[dejans]

Hi,

Thank you for the update.

Best regards,
Dejan