Author Topic: How to setup 300Kbps in RFM69HW  (Read 1117 times)

gussabina

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How to setup 300Kbps in RFM69HW
« on: April 13, 2018, 12:58:52 AM »
Hello:

I'm trying to test the 300Kbps in the RFM69HW, so I basically changed these lines;

    /* 0x03 */ { REG_BITRATEMSB, RF_BITRATEMSB_55555}, // default: 4.8 KBPS
    /* 0x04 */ { REG_BITRATELSB, RF_BITRATELSB_55555},

by

    /* 0x03 */ { REG_BITRATEMSB, RF_BITRATEMSB_300000},
    /* 0x04 */ { REG_BITRATELSB, RF_BITRATELSB_300000},

but it didn't work.... Is there something else I need to take care of?

I checked that :

FSTEP = FXOSC/219  = 61Hz  (FXOSC = 32MHz )

F_DEV = Fstep ⋅ Fdev(15,0)  (default Fdev = 0x52 -> F_DEV = 5KHz)

To ensure proper modulation;
 ( F_DEV + BR/2 ) < 500KHz

and it seems to be Ok, so I'm not sure what else do I need...

I successfully tried 115,2 Kbps, 200 Kbps and even 250 Kbps; but no luck with 300 Kbps...


BTW, will the range be affected using higher bitrate?

Thanks

Gus
« Last Edit: April 13, 2018, 01:18:16 AM by gussabina »

LukaQ

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Re: How to setup 300Kbps in RFM69HW
« Reply #1 on: April 13, 2018, 03:53:42 AM »
This is not sticky, but here you go
https://docs.google.com/spreadsheets/d/19Hm3M6nYHQl0JxDul8FUR5MApRKPj2PcxBRzim5iJ3Q/copy

that is not the only thing you need to change. With 50k fdev, you can't have 300k bitrate

ChemE

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Re: How to setup 300Kbps in RFM69HW
« Reply #2 on: April 13, 2018, 07:22:48 AM »

Felix

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Re: How to setup 300Kbps in RFM69HW
« Reply #3 on: April 13, 2018, 12:45:14 PM »
See the OTA programmer/target examples for sample 300kbps settings.