Stable WiFi ntp failing

I’m very appreciative of the Wio Terminal architecture, and that it has a communications processor RTL8720DN.
Are there any examples of a stable test suite for this implementation of Tcp/Ip over WiFi ?

I appreciate the interface pointers on how to load RTL8720DN, but from what I’m seeing is it is still pretty raw, and maybe isn’t stable.
I am digging through the interface, and its not described - so that would be OK if an API is well defined.

I have built the ntp example in and it runs for about 10 time updates at 15 minute between each update and then fails, I’ve repeated it a number of times.
The basic ntp code as listed requires an external RTC,
RTC_DS3231 rtc;
yet there is an internal RTC in the SAMD51~ so doesn’t seem like it was tested for a simple Wio Terminal before it was released into Seeed_Arduino_Sketchbook/

In building the code, there are numerous warnings about conflicts that seem to imply this is a pretty raw implementation.
C:\users\neilh77a.platformio\packages\framework-cmsis-atmel\CMSIS\Device\ATMEL/samd51/include/samd51p19a.h:547:0: warning: “LITTLE_ENDIAN” redefined
c:\users\neilh77a.platformio\packages\toolchain-gccarmnoneeabi\arm-none-eabi\include\machine\endian.h:17:0: note: this is the location of the previous definition

I am trying to integrate with another package, and many more warnings come up.

It may be that its not being set up right in PlatformIO, so any pointers if I’m doing this wrong.
My implementation is at

Hi @neilh20

Sorry for the issue caused, and yes there are some known bugs under this current firmware. We are planning to re-construct the Wi-Fi core using eRPC method instead of AT commands for now to reduce bugs. Currently BLE is under development on this framework and will be released within this month. WiFi is then after this.

Best Regards,

Thanks for getting back. Wonderful to hear.
In my experience AT cmds can take a lot of maintenance - easy to start with, but painful to stabilize.

Btw an interesting board that might provide power to Wio T -

Thanks for getting back. Hopefully the BLE is releasing this week :smiley:

Hi, how is the re-construction of the Wi-Fi core progressing?

We finished all the work except STL last Friday, finished the STL call this week, and then released the software. @jasea


Thank you very much for the very prompt update

I have been following this thread and I am a little confused.

Is STL in the Wi-Fi core or in Bluetooth?

Has the Wi-Fi core been updated?

Can we get an early ‘beta’ to try?

How are we notified of the update?

Will the Arduino IDE recognise the need to update the library or is it a manual process?

Sorry I have been waiting for a fix as consecutive (one per day) calls to NTP always fail after the initial call.
I also am hoping the new Wi-Fi core will use less memory so I can use a full screen sprite in my WI-FI application.



@stuartdd Yes, STL is integrated into WIFI Core, WIFI Core and BLE are togethe. The STL is still in development, and we have provided some demos. But we don’t have a bata release yet.


Soooo glad to see the eRPC WiFi stuff. I have an issue using it at the moment… Could you please assist.

I refered to:

For the firmware update and udate of the libraries but I get a compile error:

in file included from C:\Users\stuar\Documents\Arduino\libraries\Seeed_Arduino_rpcWiFi-master\src/rpcWiFi.h:1:0,
from C:\Users\stuar\AppData\Local\Temp\arduino_modified_sketch_4988\sketch_nov13a.ino:4:
C:\Users\stuar\Documents\Arduino\libraries\Seeed_Arduino_rpcWiFi-master\src/WiFi.h:29:10: fatal error: IPv6Address.h: No such file or directory
#include “IPv6Address.h”

I get this with my own project as well as the example (scanner) code on the above site!

I have deleted my Arduino15 directory and re-installed the boards and the libraries from scratch.

I have burned the RTL8270 fw. (Nice to see the update to the flasher)

My imports

#include “rpcWiFi.h”
#include “DateTime.h”
#include “Free_Fonts.h”
#include <SPI.h>
#include <Seeed_FS.h>
#include “SD/Seeed_SD.h”
#include “SEG_M.h”
#include “SEG_S.h”
#include “TFT_eSPI.h”
#include “lcd_backlight.hpp”

My libraries:

d----- 30/10/2020 16:34 Adafruit_BusIO
d----- 27/10/2020 09:39 Adafruit_Circuit_Playground
d----- 27/10/2020 09:39 Adafruit_GFX_Library
d----- 08/11/2020 19:42 Adafruit_GPS_Library
d----- 19/09/2020 15:43 Adafruit_ILI9341
d----- 19/09/2020 15:43 Adafruit_LED_Backpack_Library
d----- 19/09/2020 15:43 Adafruit_SleepyDog_Library
d----- 19/09/2020 15:43 Adafruit_STMPE610
d----- 30/10/2020 16:34 Adafruit_TouchScreen
d----- 19/09/2020 15:43 Adafruit_Zero_DMA_Library
d----- 19/09/2020 15:43 Adafruit_Zero_FFT_Library
d----- 19/09/2020 15:43 Adafruit_Zero_PDM_Library
d----- 19/09/2020 15:45 esp-at-lib-develop
d----- 11/11/2020 16:17 Seeed_Arduino_FreeRTOS-master
d----- 11/11/2020 16:22 Seeed_Arduino_FS-master
d----- 11/11/2020 16:16 Seeed_Arduino_rpcBLE-master
d----- 11/11/2020 16:18 Seeed_Arduino_rpcUnified-master
d----- 11/11/2020 16:15 Seeed_Arduino_rpcWiFi-master
d----- 11/11/2020 16:20 Seeed_Arduino_RTC-master
d----- 11/11/2020 16:13 Seeed_Arduino_SFUD-master
d----- 19/09/2020 15:44 Servo
d----- 19/09/2020 15:43 TinyWireM
d----- 19/09/2020 15:43 WaveHC

An update to this issue:

I was building on Windows using PlatformIO when I had the issue. I always install libraries using Arduino as I like to swap between Arduino ID and PlatformIO. My platformio.ini contains the following:

platform = atmelsam
board = seeed_wio_terminal
framework = arduino
lib_extra_dirs = C:\Users\stuart\Documents\Arduino\libraries

platform_packages = framework-arduino-samd-seeed@
lib_ldf_mode = deep

I did some experimenting and downloaded some examples that I build using tha Adruino IDE. These compiled and uploaded and now the PlatformIO build compiles and uploads OK. I cannot be 100% sure that it was building using Arduino IDE but that is all I can think of.

So now it builds and uploads. I have some issues in that the scanner (example from the WIKI) does not list my 2.4Ghz SSID. It only lists my 5Ghz channels.

I have 2 WIO devices. I swap them when I do a release. The current (live) one runs using the atWIFI and connects to my 2.4Ghz SSID, the other (dev) one uses rpcWIFI and cannot see the 2.4Ghz SSID. It will however connect the the 5Ghz SSID.

This is a bit of a problem as the range for 5Ghz is lower and I am operating at a distance. I really need it to connect to 2.4Ghz channels.

Any advise for this would be really usefull.


You can first see what channels the old (atWiFI) Wio Terminal connected in your WiFi. Then in the new (rpcWiFi) Wio Terminal connect to the wifi with specific channel like this:

Sorry I think I was not clear in my post.

I have a multi Band router. SSID ‘A’ transmits at a radio frequency of 2.4Ghz, SSID ‘B’ transmits at a radio frequency of 5.0Ghz.

I have TWO devices (WIO Terminal), one (live) is running with the original atWIFI and is connecting to ‘A’ on a regular basis. The other (dev) I use for development work and is running the new rpcWIFI. When I create a new version of the application I swap the devices (live <-> dev) over.

Currently live is using the original atWIFI and connects to ‘A’ at 2.4Ghz. The dev device is using the new rpcWIFI. It does not connect to ‘A’ at 2.4Ghz. The application is unchanged. If I change the SSID of the application on dev to use ‘B’ it connects OK.

Note that MY laptop (connected to dev via USB) lists both ‘A’ and ‘B’.

To investigate I uploaded the scanner code on to the ‘dev’ device and the list did not include ‘A’ it listed only ‘B’.

My assumption is thet the rpcWIFI is the issue. I am still investigation but could do with some advice on driving the WIO to see if I can work out what the issue is.


Sorry for misunderstanding.

So your rpcWifi Wio Terminal does not connect to the 2.4GHz SSID? Do you mean in your set-up, both wifi have different names like this:

Hi. Yes that seems to be the issue.

I have TWO SSID’s. The actual names are ‘George’, this is the 2.4Ghz and ‘Mildred’ is the 5.0Ghz. These are specific names I gave them when I configure my router.

They both use WPA2-PSK. Mildred is fixed to Channel 44 and George is set the Auto so will vary.

I have been using George up until now as the signal strength is better where I have the WIO Terminal positioned.

However now it does not list George. The Laptop sitting next the the WIO Terminal lists and connects to Both George and Mildred.


I have just tried the upgraded version again and I can now see both 2.4 and 5.0 bands. It seems to be intermittent. Somtimes I can see both and somtimes only the 5.0 band.

I will try updating the firmware again and download the latest libraries to see if there was some corruption or failure to install.



Okay this seems strange, as in our case we can connect to 2.4GHz Wifi very easy and this is the main bandwidth we used for testing.

Hey just getting back to this to try the new rpcWiFi. Looking good .
Many thanks for the example
It works for me!!.
I compiled it on platformio (yeah for an amazing tool) and it worked.
I’ve made to some modifications for some simple error handling - at this point just some basic error conditions. This is the basis of trying some stability and long term soak testing.