Igal Fatelevich

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5 years, 10 months ago.

how do i control the preamble length?

im using the sx 1280 transceiver broadcasting LORA modulation i would like to know how i can control the next parameters:

preamble lengh? header mode? crc? transmitted data?

thanks you for the help

Question relating to:

Last updated: 07 Mar 2019

1 Answer

Karen Yen
5 years, 10 months ago.

Hello Igal,

I would take a look at the sx 1280 library:

https://os.mbed.com/teams/Semtech/code/SX1280Lib/

As well as this document which describes the different features for setting preamble lengths, crc, etc:

https://www.mouser.com/ds/2/761/sx1280_81-1278114.pdf

Hope this helps!

-Karen, team Mbed

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hi karen, thank you for the answer but im still having truble finding the specific code part which sets the length. isit possible for your help please?

thank you.

posted by Igal Fatelevich 10 Jul 2018

Hello Igal,

All the functions and data types can be searched through here:

https://os.mbed.com/teams/Semtech/code/SX1280Lib/docs/tip/classSX1280.html

You should see the PreambleLength data type here:

https://os.mbed.com/teams/Semtech/code/SX1280Lib/docs/tip/structPacketParams__t.html#a9bdce80c748e82363f45671eb6528500

It looks like the SetPacketParam function sets the preamble length:

https://os.mbed.com/teams/Semtech/code/SX1280Lib/docs/tip/sx1280_8cpp_source.html#l00281

There is also a useful guide for LoRa settings on page 111 of the document I have linked previously.

Hope this helps!

-Karen, team Mbed

posted by Karen Yen 10 Jul 2018