Associate II

Solved

NFC filed is blocking the RTC count up for the SMARTAG1?

Forum|Forum|5 years ago
December 9, 2020
1 reply
842 views

I am evaluating the SMARTAG1. What I am trying to figure out is, what is the best way to handle measurement event while there is an NFC field. I have noticed in the implementation of SMARTAG1 firmware, that you are neglecting counting up the time once a synchronization event occurs if there is filed rising, which will effect the time stamp to be off by the time that tag was under RF field.

I want to know if I want to have stable Synchronization time events even if NFC filed is detected, what is the best way to handle it?

For example:

I want to record a measurement every 10 seconds. I start logging at 13:00:00 next at 13:00:10 , then I had NFC field for 3 second, my next measurement is logged at 13:00:23 instead of 13:00:20.

Is there a way to handle this issue in a better way?

Thank you very much for your help and your ideas.

This topic has been closed for replies.

Best answer by Salvatore Curti

Hi,

there is a way to handle this isuue in a better way.

In the code, in the file main.c and in the function "WakeUpTimerCallBack()" you find this lines:

/* if the phone is under the NFC... we don't increment the Counter of the numbers of wake up events */

if(RFActivityStatus != FIELD_RISING ) {

NumWakeUps++;

}

Remove the if condition and increase the "NumWakeUps" only.

Attention please:

I do not tested what could happened if a synchronization event occurs when there is a "filed rising".

You are in read mode onto the NFC EEPROM but in write mode contemporanely.

I Suppose that the NFC write operation return an error, becouse (if I remember well) it is not possible read and write simultenuosly on to the NFC EEPROM.

Again, the counter variable NumWakeUps will be restart when a new confiuration is set.

Regards,

Salvatore Curti.

Salvatore CurtiBest answer

ST Employee

Hi,