How to configure nrf52832 without the 32kHZ crystal.

RE: How to configure nrf52832 without the 32kHZ crystal.

laumung — Sun, 01 Aug 2021 17:54:33 GMT

Hi Jonathan, here is the link for ble_app_uart__saadc_timer_driven__scan_mode on Github.

nRF52-ADC-examples/README.md at master · NordicPlayground/nRF52-ADC-examples (github.com)

The problem is solved. Thanks.

RE: How to configure nrf52832 without the 32kHZ crystal.

JONATHAN LL — Wed, 21 Jul 2021 06:33:01 GMT

Currently i cant find any project that called ble_app_uart__saadc_timer_driven, could you link to your project? And what changes have you made?

the UART hardware is not different but the nrf840 does have more uart instances then the nrf52832. Could it be that you are al ready using the nrf52832 uart to something else?

From the phone screen shoot it looks like you changed to heart rate in stead of Nordic UART service.

Regards,
Jonathan

RE: How to configure nrf52832 without the 32kHZ crystal.

laumung — Tue, 20 Jul 2021 06:56:52 GMT

Hi Jonathan, I just make some progress today for the project. I found that the hardware of my board with the NRF52 DK board is on the UART port. The UART port of the nRF52832 of the DK board is connected to the debug MCU while my UART port of the MCU is floating and not connected to any other chip. I searched online and someone said should configure the RX pin of the UART port to be pullup after UART initialization. I make the correction as follows.

The firmware worked better than before. I can get the BLE advertising on iPhone through the nRF connection. But the service of the BLE seems different from the normal one shown below.

The left one is the normal NUS service and the right one is the abnormal one. The service seems different. Which code should I correct to make the NUS service works well?

BTW, I have made another board with nRF52840 for NUS service too. I didn't make any configuration with the UART port pin but it works well. The hardware of the UART is different from 52832 and 52840? Thank you for your help.

RE: How to configure nrf52832 without the 32kHZ crystal.

laumung — Fri, 16 Jul 2021 03:06:18 GMT

For the schematic, I followed the schematic QFAA with internal LDO setup in the nrf52832 datasheet as shown below.

RE: How to configure nrf52832 without the 32kHZ crystal.

laumung — Thu, 15 Jul 2021 16:22:33 GMT

Thank you Jonathan. Yes, I can share anything to solve the problem. Here is the main part of nrf52832 in schematic.

How to check out if the device works when it comes to transmitting? I have an antenna for nrf52832 on board. But based on the previous nrf52832 project I did before, the missing of antenna will only affect the signal strength. The BLE network should set up between MCU and the phone and the signal will be weaker without the antenna. Hope to get help from you. Thanks.

RE: How to configure nrf52832 without the 32kHZ crystal.

JONATHAN LL — Thu, 15 Jul 2021 15:09:40 GMT

Hi,

Do you know if the device is working correctly when it comes to transmitting ? Could you share the schematic or the schematic of just the antenna section if you don't want to share the complete thing.

Regards,
Jonathan