topic Re: wakeup from VLLS1 mode through UART and LPTIMER both how ? in Kinetis Microcontrollers

wakeup from VLLS1 mode through UART and LPTIMER both how ?

fw01 — Tue, 18 Jun 2019 07:35:07 GMT

Hello all,

@kerry zhou

For my application, i want to wake up my device from VLLS1 mode through LPTIMER as well as UART3_RX (connected with RF RX).

I am using MK20DX128VLL7 microcontroller with sensors , GSM module (UART comm.) and RF module (UART comm.).

And there is star network, where one master device and more than 10 slave device connected in on e network.

At my master device side : get all sensors data -> send on web page through GSM -> and sleep for 30min. for timer interrupt i have used LPTIMER.

At my slave device side : get all sensors data -> send that data to master device through RF transmitter. -> master RF receive that data and send that data through GSM netwrk on web page.

This is the my application.

Now i want to implement : master device in VLLS1 mode -> if data coming from RF (through UART3_RX)-> master device should wake up and transmit only master device -> again go for sleep mode -> until other slave device wake up or LPTIMER wake up.

I have checked in LLWU file for interrupt enable for UART. But i have not find UART3_RX for interrupt.

So can i not use that interrupt pin for wake up device?

i have already implemented wakeup through LPTIMER from VLLS1 mode.

Please guide me to add uart3 for interrupt wakeup form VLLS1 mode.

Thanks and Regards,

Reena

Re: wakeup from VLLS1 mode through UART and LPTIMER both how ?

mjbcswitzerland — Tue, 18 Jun 2019 10:38:05 GMT

UARTs are not LLWU sources so it is not possible to wake the processor from VLLS1 by UART reception.

However, if you connect a LLWU input in parallel with UART3_RX input then you can wake up on an edge via the corresponding LLUW pin.

If you were to move UART3 to UART1 on PTE1, for example, you then have UART1_RX and LLWU_P0 on the same pin, meaning that when you move to VLLS1 you can use its LLWU pin function and after you wake you can then use its UART_RX function without needing to connect two pins in parallel.

Regards

Mark

Complete Kinetis solutions for professional needs, training and support:http://www.utasker.com/kinetis.html
Kinetis K20:
- http://www.utasker.com/kinetis/FRDM-K20D50M.html
- http://www.utasker.com/kinetis/TWR-K20D50M.html
- http://www.utasker.com/kinetis/TWR-K20D72M.html
- http://www.utasker.com/kinetis/TEENSY_3.1.html
- http://www.utasker.com/kinetis/tinyK20.html
uTasker: supporting >1'000 registered Kinetis users get products faster and cheaper to market
Request Free emergency remote desk-top consulting at http://www.utasker.com/services.html

Re: wakeup from VLLS1 mode through UART and LPTIMER both how ?

fw01 — Tue, 18 Jun 2019 11:46:03 GMT

Hello sir,

Thanks for your response,

Unfortunately i can not move uart port from 3 to 1. But i can change low power mode. What i want is system has to go in any sleep mode and should wake up on uart3_rx data.

Will you pls suggest me any example for that ? or give me routine for that?

How can i enable interrupt for that and how can i write wake up routine for that ?

Thanks & Regards,

Reena

Re: wakeup from VLLS1 mode through UART and LPTIMER both how ?

mjbcswitzerland — Tue, 18 Jun 2019 22:30:55 GMT

See:
VLPS with continuous UART operation: https://community.nxp.com/message/421247#421247

Low power and LLWU: http://www.utasker.com/kinetis/LLWU.html
Low power videos:
- https://youtu.be/kWNlsAoMly4
- https://youtu.be/iZEMRiDmHzw
- https://youtu.be/v4UnfcDiaE4

Regards

Mark

Re: wakeup from VLLS1 mode through UART and LPTIMER both how ?

kerryzhou — Wed, 19 Jun 2019 02:08:54 GMT

Hi Reena Patel,

Mark's reply is totally correct!

UART3 can't work under the VLLS1 mode, please also note, VLLS1 recovery method is wakeup reset.

About the UART can be waked up power mode, please check the following picture.

Have a great day,
Kerry

-------------------------------------------------------------------------------
Note:
- If this post answers your question, please click the "Mark Correct" button. Thank you!

- We are following threads for 7 weeks after the last post, later replies are ignored
Please open a new thread and refer to the closed one, if you have a related question at a later point in time.
-------------------------------------------------------------------------------