Validate ADC sampling at 1 kHz

RE: Validate ADC sampling at 1 kHz

Ole Bauck — Tue, 31 May 2016 08:22:43 GMT

NRF_LOG_INIT() will initialize the log module.

Around 28 characters at 115200 will take about 1/115200 * 10 bauds per byte * 28 byte = 2.4ms, so you would not be able to print out as fast as you sample, which will lead to your buffer being filled up and eventually junk will be printed. You can use RTT instead by changing NRF_LOG_USES_UART=1 to NRF_LOG_USES_RTT=1 in the precompiler symbols. RTT is much faster (uses the debug interface). You need RTT viewer to see what you print on the PC.

RE: Validate ADC sampling at 1 kHz

Wojtek — Mon, 30 May 2016 19:23:15 GMT

you can read about each module and it's usage and initialization in SDK documentation available on infocenter. however, i suggest you to start on checking how it is implemented in examples available in SDK.

RE: Validate ADC sampling at 1 kHz

Sri_guy — Mon, 30 May 2016 18:01:15 GMT

Ok, how do I initialize log module over UART? I included the library "nrf_log.h"

RE: Validate ADC sampling at 1 kHz

Wojtek — Mon, 30 May 2016 15:03:05 GMT

I think your app crashes, because you are trying to use uninitialized LOG module. You can just use debugger and check what your program is doing...

RE: Validate ADC sampling at 1 kHz

Wojtek — Mon, 30 May 2016 14:14:58 GMT

You have not initialized log module (i dunno if you want to use UART or RTT logging, but it is not initialized anyway), so your debug output is not working.

I am not sure though you will be able to have 1k sampling with debug print at the same time... try some lower frequencies at the beginning maybe?