WICED™ Studio Forum Discussions

Keep getting those errors when connecting bonded Cysmart to CYW20719:

Status : Connection Terminated Due to MIC Failure (0x3d)

Encryption Status Event: bd ( 5a 10 0c ef 51 aa  ) res 8109

The CYW20719 hardware is CYBT_413034_EVAL.

Clients are Samsung TAB E 7” and Tab A 8” tablets with Android 4.4.4, 5.0.1 and 6.0.1

This error happens:

1. Always if I pair let say Cysmart client1 on Android device 1 and disconnect, then pair another let say Cysmart client2 on Android device 2 and disconnect, RESET the CYW20719, then when return back to device1 and try to connect to CYW20719 (on Cysmart button on the right side shows ‘Paired’) so just click on the name of the CYW20719 a.k.a ‘Hello’ to reconnect and always (100%) will get ‘Connection Terminated Due to MIC Failure (0x3d)’.  So there is some logic to get error in this situation, because ‘hello_sensor’  code stores bonding info only for 1 bonding, but why this error will be MIC – isn’t MIC (message integrity check)  something similar to CRC?
2. Random – this is the most annoying problem, because it happens when only one Device is bonded and  only this device trying to reconnect – sometimes connect, sometimes fail with the same MIC failure error (0x3d). And I tried plenty of different devices and Android OS versions: 4.4.4, 5.0.1, 6.0.1 and happened only with CYW20719.

So I already rise this problem couple months ago, but haven’t receive any solution (neither on any of the bugs I reported so far ☹ ), but at least:

Do you have some sniffer tool that could capture raw packets (incl. MIC) in the communication client <> server so to compare what is the difference when reconnecting go smooth and when fail?

Either there is something wrong on the Cypresses BT stack side or something in the timing parameters/syncs in the connection ☹   The only clue I could guess – slower processors with Android have more MIC failures than faster ones ☹ , but when I try reconnecting bonded CC2540 from TI, don’t have any problems neither with Cysmart, nor nRf Connect or other BLE Android clients on the same Android devices that fails with CYW20719 ☹

….

17:29:09.988 1 hello_sensor_management_cback: 17

17:29:09.992 1 Advertisement State Change: 0

17:29:09.992 1 ADV stop

17:29:09.994 RCVD [1] Event from HCI.  Name: HCI_Encryption_Change   (Hex Code: 0x08  Param Len: 4)

17:29:09.994                                   Status : Connection Terminated Due to MIC Failure (0x3d)

17:29:09.994                        Connection Handle : 64 (0x0040)

17:29:09.994                        Encryption Enable : 0 (0x00)

17:29:09.996 1 hello_sensor_management_cback: c

17:29:10.003 1 Encryption Status Event: bd ( 5a 10 0c ef 51 aa  ) res 8109

17:29:10.007 1 encryp change bd ( 5a 10 0c ef 51 aa  ) res: 8109

17:29:10.010 RCVD [1] Event from HCI.  Name: HCI_Disconnection_Complete   (Hex Code: 0x05  Param Len: 4)

17:29:10.010                                   Status : Success (0x00)

17:29:10.010                        Connection Handle : 64 (0x0040)

17:29:10.010                                   Reason : 61 (0x3d)

17:29:10.010 Connection Terminated Due to MIC Failure

17:29:10.014 1 connection_down 5a 10 0c ef 51 aa  conn_id:1 reason:61

…

Infineon AIROC Wi-Fi/Bluetooth Combo STM32 Expansion Pack is an extension of the CMSIS-Pack standard established by Arm. The pack is compliant with the full CMSIS-Pack standard, with additional requirements/restrictions on the final pack to meet the STM standard.

This SW pack uses libraries from the Infineon ModusToolbox environment. 

• Infineon GitHub landing space - https://github.com/Infineon/stm32-connectivity/releases
• Infineon AIROC Wi-Fi/BT STM32 Expansion Pack v1.4.0 – https://github.com/Infineon/stm32-connectivity/releases/download/release-v1.4.0/Infineon.Connectivit...
• Infineon AIROC Connectivity STM32 User Guide v1.4.0 – https://github.com/Infineon/stm32-connectivity/blob/release-v1.4.0/Documentation/STM32ConnectivityEx...

What's Included?

• Infineon AIROC Wi-Fi / Bluetooth Combo Release for STM32H7xx, H5xx, U5xx & L5xx MCUs family

What Changed?

v1.4.0

• Added STM32H5xx support
• PAL improvements and fixes
• New Examples added for STM32H747I-DISCO and STM32U575I-EV
• Wi-Fi offload - TCP/IP Keepalive offload

Supported STM32 Boards and MCU

• STM32H747I-DISCO Discovery kit and STM32H7xx
• NUCLEO-H563ZI board and STM32H5xx
• STM32U575I-EV Evaluation board and STM32U5xx
• STM32L562E-DK kit and STM32L5xx

Supported Connectivity Modules

Infineon's CYW43xxx Wi-Fi-BT combo chip family:

• CYW43012
• CYW43439 / CYW43438 / CYW4343W
• CYW4373 / CYW4373/E

Example apps inside the Pack

Wi-Fi Scan Example

This example initializes the Wi-Fi device and starts a Wi-Fi scan without any filter and prints the
results on the serial terminal.

Refer to Projects/STM32H747I-DISCO/Applications/wifi_scan/readme.txt for more details

Wi-Fi Onboarding with Bluetooth LE Example

This example demonstrates a simultaneous usage of Wi-Fi and BLE functionality of CYW43xxx combo
devices. It uses BLE on the combo device to help connect the Wi-Fi to the AP.

Refer to Projects/STM32H747I-DISCO/Applications/ble_wifi_onboarding/readme.txt for more details

Azure RTOS NetXDuo Wi-Fi UDP echo server

This application provides an example of Azure RTOS/NetXDuo stack usage. It shows how to develop a
NetX UDP server to communicate with a remote client using the NetX UDP socket API.

BLE Hello Sensor Example

This code example demonstrates the implementation of a simple Bluetooth Stack functionality in GAP
Peripheral role. During initialization the app registers with LE stack to receive various notifications
including bonding complete, connection status change and peer write.

Refer to Section BLE Hello Sensor Example in STM32 connectivity expansion pack user guide for more details.

Wi-Fi TCP keepalive offload

The TCP keepalive offload feature of the Low Power Assistant (LPA) improves the power consumption
of your connected system by reducing the time the Host needs to stay awake to support a TCP keepalive
request. This example describes how to enable TCP keepalive offload and configure four different
sockets for TCP keepalive that can be incorporated into your project from LPA Middleware.

Refer to Projects/STM32H747I-DISCO/Applications/wifi_tko/readme.txt for more details.

Compatible Software

Future release - v1.5.0

• Add Infineon Wi-Fi 6/6E combo chip (CYW55573 - 2x2 Wi-Fi 6/6E, CYW55513 - 1x1 Wi-Fi 6/6E) support.
• TCPKA keepalive (payload) offload with multiple sessions.
• Wake-on-WLAN - wowlpf support for remote wake-up.
• TLS over TKO
• MQTT keepalive

More information

• README.md
• STM32 Connectivity Expansion Pack User Guide
• Cypress Semiconductor, an Infineon Technologies Company
• Infineon GitHub
• ModusToolbox