topic Re: using kinetis l series with internal oscillator in Kinetis Microcontrollers

using kinetis l series with internal oscillator

okaner — Mon, 28 Apr 2014 06:55:50 GMT

Hi all,

I want to start using "MKL04Z32VFM4". I have used kinetis k series before. I have 2 question before design PCB. If anyone help me, I appreciate.

1) Is it possible to use 4mhz fast internal oscillator as system clock.

2) I want to use UART module at 1000000 (1Mbaud). is UART module of this MCU capable of running this baud rate.

- I used PE to use internal fast oscillator and setting uart to 1Mbaud, I did not faced with problem. I just want to get confirm before designing PCB.

Thank you...

Re: using kinetis l series with internal oscillator

jeremyzhou — Wed, 30 Apr 2014 03:42:49 GMT

Hi Okan

Thank you very much for your focus on Freescale Kinetis product. I am glad to provide service for you.

After read KL04's reference manual, I'm sure that your assumption could work out.

If you have any other questions, please feel free to contact with me.

Have a great day.

Ping

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Re: using kinetis l series with internal oscillator

perlam_i_au — Wed, 30 Apr 2014 21:49:09 GMT

Dear Okan ERCAN:

For your first question I guess you are ask because of the 4MHz IRC internal generator on the MCG, in this case you cannot use this clock directly as system clock, please see on the clocking diagram, if you want to have a system clock you should configure which Input signal you want for MCGOUTCLK and then configure OUTDIV1 and CG to get the specific system clock frequency you want.

For UART case you will notice that formula to calculate bad rate not only depends of the clock source for UART module, you should also consider OSR (UART0_C4[OSR]) and SBR (UART0_BDH[SBR] and UART0_BDL) values, as is described on the formula:

Baud Rate = Module clock / ((OSR+1) x SBR)

You need to consider all these parameters to verify if you could achieve a specific baud rate, based on the frequencies normally used on this module the common used baud rates (like the ones in the baud rate list on the hyperterminal) could be achieved, please also verify which module clock have you selected.

Regard PCB design I will recommend you the AN4747, EMC Design Tips for Kinetis L Family I hope you could find interesting information here.

Have a nice day,
Perla Moncada

Re: using kinetis l series with internal oscillator

okaner — Thu, 01 May 2014 01:45:43 GMT

Many tanks to both of you. I will also reply the results after I produce my PCB. I will use Kinetis L series for our touch buttons in smart home system. I used K series as a main server. But it would be good if we change it with a more powerful MCU and MAC57Dxxx MCUs perfectly fits for my requirements . So I really wonder, when does MAC57Dxxx MCUs become available. Is there any estimated date, thank you all...

Re: using kinetis l series with internal oscillator

jeremyzhou — Sun, 04 May 2014 03:13:17 GMT

Hi Okan,

Thanks for your reply.

Regarding to the MAC57Dxxx's final launching time, I also don't know and can't provide any estimated date.

Thank you for understanding.

Have a great day,
Ping