FRDM K64f mbed CLoud client integration with ESP8266(Wifi)

I am using mbed cloud client example code Version Release 1.3.3


my code is compiled successfully on mbed online compiler.

But I am getting runtime issue : Error code 12: ConnectDnsResolving Failed.


I just searched cloud documents, and updated mbed_device_credential file also, Error is not resolved

Currently i am using SD card, if i dont want to use SD card, then where to make changes.

Please Provide Proper Document for released code, plz Dont provide link of Entire Mbed Cloud documenation.


I have compiled this code with Mbed CLI tool for FRDM k64F, with Ethernet, i have followed all the steps as mentioned in Document.

Note, FRDM k64F board is having only 1024 KB of Flash memory, but genrated combined.hex size is around 1215 KB, so Could not download it in FRDM.

Is it the right behaviour ???


DNS error means that the device is not able to resolve Mbed Cloud URL address to IP address. That normally happens when your device is running behind some network firewall and its not able to translate the URL.
Can you try to use any open WiFi hotspot to check if the device is able to resolve Cloud URL?


Thank you.

.bin file is stored in FRDM flash memory.

Could you please tell me why SD card is Mandatory ?? what is stored on SD card.

and is there is any way to remove SD card Dependecy ??


At the moment the FRDM K64F PC-based flashing procedure requires SD card to store the binary prior to flashing.
Please refer to FRDM OpenSDA interface.

btw, I recon your SD card size is reported as 1MB. You might want to consider updating CMSIS-DAP Interface Firmware to newer version from board page (will forward to NXP site). Update allows storing larger files to SD card, however it will not lift the K64F internal flash limitations.


The interface firmware on your board is out of date. This is a known issue with older boards. Please update your interface firmware.

As for the SD card issue, it is required to have external storage of some sort to use cloud services. That said it can be an SD Card, external SPI or I2C Flash or really anything else. Cloud client doesnt actually care about the type as long as it has a block device driver and can be used by the file system.

Here is some example code that uses non-SD Cards. (Bonus, this board has WiFi built into it, so if you want to use Wifi i’d suggest using this board as well)