💬 Arduino Pro Mini Shield for RFM69(H)W

[scalz]

@pepson
let's recap, I'm not sure you got it..
Says you have a VIN of 5 or 9V, and you connect it to your arduino. On the arduino board you have a ldo. So:

• 5V Arduino variants will convert the VIN to a 5V VCC supply to you microcontroller (let's call it atmel, or 328p it's shorter). At this moment the atmel is running fully on 5v. If you set an IO to HIGH or =1, it will output 5V! And it's the same for SPI that you connect to your radio module. You thought you could apply a lower voltage to the radio module by applying an external 3V ?? Can't work, because SPI has datain and dataout. Dataout from atmel to radio will be 5v!!
• 3V arduino variants will convert your VIN (5, 9V etc..) to 3v. The atmel will run on 3v, its pins and peripherals too, so no problem for the dataout above.

I can't explain better, or maybe you should use a 3v arduino, and add a fet to drive your relay from 5v.
I would prefer this way (level shifting a basic io, than level shifting the spi bus)

[zboblamont]

@pepson This reminds of that famous quotation "Any ship can be a Minesweeper..."
"Once...."

[gohan]

@pepson if you need to run a relay, just get an optoisolated relay board and you can use a 3.3v arduino or raspberry without problems.

[pepson]

@scalz
What is "fet" ?

When i use Arduino Pro Mini 3V i can put power 5V to Arduino and he step down to 3V ? Arduino will not destroy ?

[pepson]

@gohan said in 💬 Arduino Pro Mini Shield for RFM69(H)W:

@pepson if you need to run a relay, just get an optoisolated relay board and you can use a 3.3v arduino or raspberry without problems.

I dont uderstand ?
Relay is power by 5V. But if i use Arduino Pro Mini 3V he give to relay 3V and relay probably not working on power 3V...
Sorry i am beginner...

And i can use this logic level converter

https://pl.aliexpress.com/item/8CH-IIC-I2C-Logic-Level-Converter-Bi-Directional-Module-DC-DC-5V-to-3-3V-Setp/32238089139.html?spm=a2g17.search0104.3.299.voV8Dr&ws_ab_test=searchweb0_0,searchweb201602_4_10152_5000015_10151_10065_10344_10068_10342_10343_51102_10340_10341_5130015_10084_10083_10304_10307_10301_10312_10059_10313_10314_10534_5790011_100031_10604_10103_10594_5060015_10142,searchweb201603_32,ppcSwitch_4&algo_expid=1efe59eb-1872-47dd-8d87-8a30137c624f-24&algo_pvid=1efe59eb-1872-47dd-8d87-8a30137c624f&rmStoreLevelAB=5

??

[gohan]

Get one of these and you can use whatever arduino you want
https://www.aliexpress.com/item/With-Optocoupler-4-Channel-4-channel-Relay-Modules-Relay-Control-Panel-PLC-Relay-5V-Four-Way/32458001101.html

And maybe a new rfm69 module since you probably already killed the one you used.

[pepson]

@gohan

Radio works ok.

But from where i get 5V for Relay ?

[gohan]

@pepson if you have the 5V power supply, you get it from there

[zboblamont]

@pepson If you go to 3v Arduino, the answer seems likely to be a 3v relay, either a package as @gohan suggested or roll your own, no ?
FYI, I have a 3v3 node with a RFM69 which has to run a 5v sensor but the number of spare pins is limited, so after many trials and tribulations, am using a 5v Arduino to run and task the sensor with the results being passed back via I2C to the 3.3 device via level converter, all initiated via a single DPDT relay which switches the booster and 5v unit on and off after each cycle..
"Radio works ok." is today, tomorrow is another day...

[muguran]

Hi,

According to this connection guide https://www.mysensors.org/build/connect_radio the pro mini D2 will connect to RFN69's DI00.
But the shield seems to connect D4 to DI00.
Is it OK? Or we need to adapt our sketches?

Thanks

[NeverDie]

@muguran said in 💬 Arduino Pro Mini Shield for RFM69(H)W:

But the shield seems to connect D4 to DI00.

Actually, no. DIO0 does connect to D2 on this shield, so there should be no issues. :)

[muguran]

It seems that I've got another board: it have 4 holes above GND, D2, D3 and D4, and DI00 is connected to the one for D4.
Is this an old version?
I've ordered at the beginning of this year.

[gohan]

@muguran post a picture if you can

[muguran]

[NeverDie]

@muguran
Yes, that's an older version. A fix is discussed in the comments above.

[pepson]

@muguran

Hi
Where i can buy this pcb to connect RFM69HW with Arduino Mini Pro ?

[NeverDie]

@pepson said in 💬 Arduino Pro Mini Shield for RFM69(H)W:

@muguran

Hi
Where i can buy this pcb to connect RFM69HW with Arduino Mini Pro ?

Click "buy" at this link: https://www.openhardware.io/view/268/Arduino-Pro-Mini-Shield-for-RFM69HW

[pepson]

@neverdie
Thanks

[Tmaster]

hi.i know that discoussion have some months ,buti'm only doing my rfm69 conversion from nrf24 ,now.
second this picture here, i can leave digital pin 2 from arduino direct to rfm69 d0 pin. Without anylevel converter when use a 5v arduino
is that true? will not fry because that?
i will use a ams1117 3.3v regulator for power rfm69c from my 5v pro minis

sorce:https://learn.sparkfun.com/tutorials/rfm69hcw-hookup-guide

[gohan]

If I remeber right that pin is used as input so the RFM69 is not receiving any 5v signal. In addition there are people claming they have the RFM69 module working on 5v on data pins and 3.3v on vcc, but I hardly suggest to do it.