e220 spreading factory issue

[frogg1ven]

Hi, I'm working on project where I'm using code similar to SX126x_Receive_Interrupt.ino, but I wanted to use e220-900m30s, so I declared class like that:
LLCC68 radio = new Module(5, 25, 32, 33);
In my previous code (where I used e22-900m30s) I initialized lora like this:

int state = radio.begin();
radio.setFrequency(869.5);
radio.setBandwidth(125.0);
radio.setSpreadingFactor(9);
radio.setOutputPower(22);

and it works fine, so I tried here do it same way, but I have status code -707.
I found in some other post that this may work:
int state = radio.begin(869.5, 125.0, 9, 7, SX126X_SYNC_WORD_PRIVATE, 22, 8, 0);
and with this initialization code is working but I'm not receiving data from transmiter.
Transmiter (on sx1262, e22) initialization code here:

int state = radio.begin();
radio.setFrequency(869.5);
radio.setBandwidth(125.0);
radio.setSpreadingFactor(12);
radio.setOutputPower(19);  

I would like to ask about two things, first what is the difference between one line and set functions initializations,
and second, what may be the problem that my receiver is not racaive any data? With two e22 its working great.
Could you help me please?
Regards.

[jgromes]

what is the difference between one line and set functions initializations

The single line begin method sets TCXO voltage to 0 (among other things), which disables TCXO and enables XTAL. You have to select correct crystal type in order for the module to be able to perfrom frequency calibration, so your module is probably using XTAL.

what may be the problem that my receiver is not racaive any data

You're transmitting at spreading factor 12, and trying to receive at spreading factor 9, which is not possible. All devices in the network must use the same spreading factor.

[jgromes]

No, you have to set output power based on the power amplifier your module is using. For example, E22 has a +26 dB amplifier, so to get +30 dBm of output power, you have to setOutputPower(4);, becuase 4 + 26 = 30.

You're using E220, and I don't know if it's using the same power amplifier as E22, but I imagine it might, since it's for the same freqency band.

[frogg1ven]

thanks for reply, I'll check that

[frogg1ven]

@jgromes
E220-900m30s has yp2233w power amplifier, if you need to know

Should I setOutputPower(1) and TX enable to achieve 27 dBm of output power, right?

[jgromes]

Thanks for the photo, it looks exactly like my E22 and has the same PA, so that confirms that theory.

Should I setOutputPower(1) and TX enable to achieve 27 dBm of output power, right?

Yes, that should be correct.

[frogg1ven]

thanks