Still retained in debug mode nrf51822

RE: Still retained in debug mode nrf51822

Satheeshkumar — Tue, 29 May 2018 10:31:23 GMT

thank you for your response. let me check and update soon.

RE: Still retained in debug mode nrf51822

Håkon Alseth — Tue, 29 May 2018 09:15:53 GMT

Hi,

Based on this information, it is very unlikely that your issue is due to entering debug mode:

[quote user="yuvasatheesh"]

sorry for late response. it was the pin reset by SWDIO/nReset pin. I have disabled all the software reset in my code.

I checked, there is no any external power up. we used bat42 diode to isolate the power to the nrf51 chip.

it is the very very huge issue for me. I have used RTC for the calendar, due to unnecessary reset, the RTC also resetting the calendar value.

to avoid this issue, I have written the current calendar value in flash memory for every minute. even though, still persist the lagging of time.

I am sure, the reset has happened by a chip which has changed to debug mode unnecessarily. please help me.

[/quote]

Debug mode is entered if SWDCLK goes high, and SWDIO goes low. SWDCLK cannot go high, as you have directly grounded that pin.

What you are describing sounds like an assertion occurring in your application, or that you have noise in your design causing the SWDIO pin to be dragged low.

What I recommend is that you enable blocking assertions in your firmware (add the preprocessor define "DEBUG" to your project) and also check the RESETREAS register upon reboot, then update this thread with the debug information you get if one of these states occurs.

Best regards,

Håkon

RE: Still retained in debug mode nrf51822

Satheeshkumar — Mon, 28 May 2018 12:08:51 GMT

Hi Alseth,

sorry for late response. it was the pin reset by SWDIO/nReset pin. I have disabled all the software reset in my code.

I checked, there is no any external power up. we used bat42 diode to isolate the power to the nrf51 chip.

it is the very very huge issue for me. I have used RTC for the calendar, due to unnecessary reset, the RTC also resetting the calendar value.

to avoid this issue, I have written the current calendar value in flash memory for every minute. even though, still persist the lagging of time.

I am sure, the reset has happened by a chip which has changed to debug mode unnecessarily. please help me.

RE: Still retained in debug mode nrf51822

Håkon Alseth — Thu, 24 May 2018 08:17:33 GMT

Does this occur on one specific module, or do several show this issue?

Just to confirm: A "hard reset" means that you are physically removing power to the nRF and applying it again afterwards?

You could also measure VDD_NRF after removing the battery to see if there's anything external trying to power up the nrf.

Best regards,

Håkon

RE: Still retained in debug mode nrf51822

Satheeshkumar — Wed, 16 May 2018 11:49:00 GMT

yes UART had removed and disabled UART module before sleep

RE: Still retained in debug mode nrf51822

Turbo J — Wed, 16 May 2018 09:58:38 GMT

Did you leave the UART connected? This can reverse-supply the chip via the RX pin, and could prevent the POR because VCC never drops low enough.

Remember that UART idle is HIGH.

RE: Still retained in debug mode nrf51822

Satheeshkumar — Wed, 16 May 2018 04:19:23 GMT

yes exactly, (~1.214mA) current has retained. at that time j-link was not connected

RE: Still retained in debug mode nrf51822

Håkon Alseth — Tue, 15 May 2018 17:53:45 GMT

Hi,

What is a hard reset? In order to exit debug mode, you need to either power cycle, or use "nrfjprog --pinreset".

Normally, the current consumption is 1.2mA when you're in debug mode. Are you seeing exactly 1.0 mA?

Does the current consumption change if you disconnect the UART connection going from the nRF to the external device?

Best regards,

Håkon

RE: Still retained in debug mode nrf51822

Satheeshkumar — Tue, 15 May 2018 11:05:59 GMT

thanks for the response. after UART communication, the chip successfully executes sleep function. but it still retains 1 mA, even though I had disabled UART function before sleep there is no any HFCLK module running. And also the chip has reset sometimes automatically. this is purely debugging mode issue.

RE: Still retained in debug mode nrf51822

Turbo J — Tue, 15 May 2018 10:37:32 GMT

The "debug mode" can only be switched OFF by a power cycle or the debugger itself.

For the JLink commander, I use the following commands to switch debug mode off:

if swd
speed 2000
connect

readDP 1
writeDP 1 0
q

First 3 lines are to connect to the chip. After executing these commands you should see a drop in current consumtion.

Note that enabling the UART would also cause about 1mA current consumtion, as this requires the HFINT or HFCLK to be up and running.