(Solved) Help with WGT51822-S2 module

RE: (Solved) Help with WGT51822-S2 module

Roger Clark — Fri, 11 Dec 2015 10:12:57 GMT

Sorry for not replying sooner.

The issue was definitely because these modules don't have the 32kHz crystal and most example code is setup to require the 32kHz crystal

To prove this, I found a 32kHz crystal, and soldered it to the module and all my example code now works fine.

BTW. I found out the module is actually a Wireless-tag.com WGT51822-S2, but was this was not shown in the AliExpress listing.

I'm not sure how to mark this thread as resolved, so please mark this question as answered if you can

Thankyou again for all your help

Cheers

Roger Clark

RE: (Solved) Help with WGT51822-S2 module

ovrebekk — Wed, 09 Dec 2015 09:20:03 GMT

I am happy to help Roger. Feel free to accept the answer if you feel the issue is resolved :)

RE: (Solved) Help with WGT51822-S2 module

Roger Clark — Mon, 07 Dec 2015 10:16:07 GMT

Thanks Torbjørn

I have managed to get the module working using mbed (online), by using the "platform" of the "Switch Science HFM1017" - which I know does not have a 32khz crystal. If I download the hex file from mbed and flash using that. It all works.

So, I have exported all the files so that I can compare with the local set I had been using (which were originally exported from mbed by RedBearLabs some time ago)

I have the SDK and I had Eclipse setup on one machine, but I'm now using a new PC, so I have to set it up all over again :-(

I think I need to read the nRF51 programming manual, as I thought I had made all the necessary changes to use the RC osciallator instead of the Crystal oscillator, but I must have missed something

Anyway. Thanks again for your help. Cheers

Roger

RE: (Solved) Help with WGT51822-S2 module

ovrebekk — Mon, 07 Dec 2015 10:04:45 GMT

It should be possible to change the LF clock source in mbed, but I am not very familiar with the online mbed compiler and haven't been able to figure out where to change it... You can also download the official SDK, which has several BLE examples supporting Eclipse/GCC, and allow you to set the LF clock source to either external or internal (with calibration). The SDK can be downloaded here: developer.nordicsemi.com/.../

RE: (Solved) Help with WGT51822-S2 module

Roger Clark — Sat, 05 Dec 2015 20:27:13 GMT

I still have not managed to get these modules to work.

However I have identified them as a Wireless-tag WT51822-S4AT, which is the same as the WT51822-S2 except comes preflashed with some AT command firmware, which i have erased

www.wireless-tag.com/.../26.html

I checked the mbed codebase I'm using and I changed the #define so that the module would use the RC oscillator, however it seemed to make no difference, and the module seems to fail to start up.

Unfortunately I cant seem to find any example code for this module.

Does anyone have any example code for Eclipse / Gcc for modules without the 32khz crystal

RE: (Solved) Help with WGT51822-S2 module

Roger Clark — Thu, 03 Dec 2015 09:38:46 GMT

@Torbjørn

Yes.

I'm using the S130 soft device from the Version 9 SDK

I'll need to track down where in the code this is currently getting setup. I did a quick search through the codebase I'm using, (mostly from mbed) and I can't see anything like SOFTDEVICE_HANDLER_INIT

Sorry if I seem vague about this,but I'm using a modified version of the RedBearLab's firmware for the Arduino IDE, as it compiles under GCC.

And I'm not currently familiar with how the code is structured.

I am however very familiar with embedded development as I am webmaster on www.stm32duino.com and host the Arduino_STM32 repo's on my github account.

RE: (Solved) Help with WGT51822-S2 module

ovrebekk — Thu, 03 Dec 2015 09:23:49 GMT

A quick comment: If you are using a BLE example with a SoftDevice, and you need to change the 32k clock source, you need to change the following line in main.c:
SOFTDEVICE_HANDLER_INIT(NRF_CLOCK_LFCLKSRC_XTAL_20_PPM, NULL);

To use the internal 32k source change the clock parameter to something like this instead: NRF_CLOCK_LFCLKSRC_RC_250_PPM_TEMP_8000MS_CALIBRATION

RE: (Solved) Help with WGT51822-S2 module

Roger Clark — Thu, 03 Dec 2015 05:41:15 GMT

Thanks

It looks like the mbed file I'm using has been updated since I took snapshot (another long story)

So it now appears to include a timeout on the startup check (which my file doesnt have)

github.com/.../system_nrf51.c

In fact, the newer version of the file has been refactored, and looks like it has other improvements

I'll need to contact the original author of the code - who took the snapshot of the mbed cmsis and ask him whether he thinks I can just grab the latest cmsis from mbed or whether he made some changes

I suspect he just took a snapshot, and copied the files rather than using the github submodule system

But I won't be able to contact him until tomorrow as he is in Canada and they will be asleep by now

Anyway, I think you have solved this mystery.

Thanks

Roger

RE: (Solved) Help with WGT51822-S2 module

frogofmagic — Thu, 03 Dec 2015 05:31:45 GMT

I'm not familiar mbed, but if you don't have 32K crystal, you can set the clock source to 16M. I saw the link you posted, it might be help. NRF_CLOCK->LFCLKSRC = (CLOCK_LFCLKSRC_SRC_Xtal << CLOCK_LFCLKSRC_SRC_Pos);

to..

NRF_CLOCK->LFCLKSRC = (CLOCK_LFCLKSRC_SRC_RC << CLOCK_LFCLKSRC_SRC_Pos);

or to..

NRF_CLOCK->LFCLKSRC = (CLOCK_LFCLKSRC_SRC_SYNTH << CLOCK_LFCLKSRC_SRC_Pos);

Maybe you can try it.

RE: (Solved) Help with WGT51822-S2 module

frogofmagic — Thu, 03 Dec 2015 05:23:27 GMT

The program is MDK-ARM uVision V5.

RE: (Solved) Help with WGT51822-S2 module

Roger Clark — Thu, 03 Dec 2015 05:21:01 GMT

Umm

Looks like this may be the issue

developer.mbed.org/.../

i.e there is code which waits for both the 16Mhz and 32khz clocks to start but the 32khz without any form of timeout (in the mbed cmsis ) :-(

There wasn't an answer to that question on the mbed forum, so I guess I'll need to manually work out what mbed uses the 32khz clock for and whether its necessary or whether there is a work around

i.e is the 32khz clock normally essential ?

RE: (Solved) Help with WGT51822-S2 module

Roger Clark — Thu, 03 Dec 2015 05:18:01 GMT

Which program did the screengrab come from?

I'm building just using Make rather than using a GUI build (long story).

I know that the AC and AA have different build settings, because of the difference in the size of RAM, but I was not aware of any other differences.

In fact as far as I was aware my build target was set for 16k RAM

I'm using this WaveShare development board which uses this module

www.waveshare.com/.../core51822.htm, (actually I have 3 RF modules like this and they are all QFAC)

Looking at the schematic, it has a 32KHz osc

www.waveshare.com/.../Core51822-Schematic.pdf

I don't have a schematic for the module from AliExpress, but I can only see what looks like the 16Mhz crystal and not a 32khz osc

I'll need to look through my code (a lot of which came from mbed) to see if there is a dependency on the 32khz osc

RE: (Solved) Help with WGT51822-S2 module

frogofmagic — Thu, 03 Dec 2015 04:51:05 GMT

1.The module you post from AliExpress, it seems no 32.768 crystal. Did you check it?

2.The AC and AA need different build option, make sure you change to right one.