ble_app_uart_c problem using a WT51822-S4AT board

RE: ble_app_uart_c problem using a WT51822-S4AT board

Sepehr1989 — Thu, 19 Jul 2018 06:54:39 GMT

Thank you so much.

It was my problem too, but solved

RE: ble_app_uart_c problem using a WT51822-S4AT board

MartinBL — Mon, 16 Apr 2018 11:42:15 GMT

Ok, so can we consider this case as closed?

I'll be traveling the rest of the week, but someone else will handle your other ticket.

Martin

RE: ble_app_uart_c problem using a WT51822-S4AT board

samuel.zetterlund — Mon, 16 Apr 2018 08:11:39 GMT

Hi again,

Now it's my time to apologize for the late answer. I had to stall this issue for quite some time and focus on other things with this project and now when I returned to this issue, the problem I faced earlier seems to be gone.

I didn't change anything to the code (or at least I don't think so) and now the central scans for peripherals and it connects to the peripheral. However, I can't seem to send anything from the central or peripheral. See this ticket:

devzone.nordicsemi.com/.../wt51822-s4at-uart-problem-board-can-receive-data-but-not-send

RE: ble_app_uart_c problem using a WT51822-S4AT board

MartinBL — Fri, 23 Mar 2018 14:35:51 GMT

Hi,

Sorry for the late response.

Have you made any progress?

If not, what SDK and Softdevice versions are you using? And are you using an example to get started?

I was not able to find a good datasheet for your module, but if it is this one, you can see that it doesn't have any external LF Crystal, so using NRF_CLOCK_LFCLKSRC_XTAL_20_PPM is out of the question. Using NRF_CLOCK_LFCLKSRC_SYNTH_250_PPM should always work though.

RE: ble_app_uart_c problem using a WT51822-S4AT board

samuel.zetterlund — Tue, 13 Mar 2018 09:45:11 GMT

I can add that the working peripheral example has the following clock settings:

In main header

#if MODULE_WT
#undef NRF_CLOCK_LFCLKSRC
#define NRF_CLOCK_LFCLKSRC {.source = NRF_CLOCK_LF_SRC_SYNTH, \
.rc_ctiv = 0, \
.rc_temp_ctiv = 0, \
.xtal_accuracy = NRF_CLOCK_LF_XTAL_ACCURACY_20_PPM}
#endif

In ble_stack_init:

nrf_clock_lf_cfg_t clock_lf_cfg = NRF_CLOCK_LFCLKSRC;

// Initialize SoftDevice.
SOFTDEVICE_HANDLER_INIT(&clock_lf_cfg, NULL);

The central example looks a bit different. In ble_stack_init, the SDK example doesn't pass a struct to SOFTDEVICE_HANDLER but only a defined value as:

SOFTDEVICE_HANDLER_INIT(NRF_CLOCK_LFCLKSRC_SYNTH_250_PPM, NULL);

When setting the clock source to NRF_CLOCK_LFCLKSRC_SYNTH_250_PPM, I get the error code 7 as I wrote earlier.

However, when setting the clock source to NRF_CLOCK_LFCLKSRC_XTAL_20_PPM, I get the error code 0x1000.