nRF52 SDK 0.9.2 temperature example uart problem

[HSPalm]

Hi, Using the NRF52 DK PCA10040, I have built and loaded the KEIL temperature example project (C:\nRF52_SDK_0.9.2_dbc28c9\examples\peripheral\temperature\pca10036\arm5_no_packs) to flash. UART pins are 5, 6, 7 and 8 by default, haven't touched the solder bridges so both female headers are still connected to those pins.

I see no data in my terminal program, neither do I see anything with a scope on the TX pin. It's supposed to transmit every 500ms. When I debug the code I see the tx_buf fills up with the correct characters for each iteration of the main loop, until its full.

I tried to disable hardware handshaking but the problem persists.

What should I look for next?

[Vidar Berg]

Hi, are you using the on-board Segger chip for as UART <-> USB bridge (default)? I did work without any changes when I tried it here.

One thing to try is to update to the latest Segger driver if you haven't already -> download link and see if it makes any difference. It should enumerate as "Jlink CDC UART PORT (com xx) in device manager once the CDC driver is installed.

Attachement:

52_temp_example.hex

[HSPalm]

Thanks for answering. Yes, I use the default method of bridging via the Segger chip. All though I am not so sure this is where the problem lies, cause I never see any activity on the UART pins and the buffer is never emptied.

I did update the J-link driver.

[Vidar Berg]

Please try to following to ensure we are doing the same:

• Do a complete flash erase
• Program the attached temperature example
• Do a system reset
• Connect with a serial terminal (Tera Term,..) and set the baudrate to 38400

[HSPalm]

Did what you said now, used your .hex file. Unfortunately no difference.

I used nRFgo Studio:

1. Pressed "Erase all"
2. Loaded your .hex and programmed it via "Program Application" tab.

Reset the board and connected to computer via USB again.

Then used Terminal (by br@y) to monitor the serial port:

1. Settings: 38400,8,N,1, tried both with and without handshaking
2. No incoming data

Please see attached photos "attached": goo.gl/.../EeBRwh5CWfTAeQUT9

[Vidar Berg]

I've not used the br@y terminal before, but it work fine when I tried it now. However, a colleague of mine have that have had varying success with it, he has experienced that it worked fine on some setups while failing on others. Not sure why that is, but could you please try with Putty or Tera Term to narrow down the problem?