Unexpected behavior using SW vs. HW SPI on ESP32 with the SX127x LoRa module

OK, so I've replaced the pins with the ones you mention--but still struggle a little 🙂!

Setup now looks like this (only the pins has changed):

const PIN_SCK = D18;
const PIN_MISO = D19;
const PIN_MOSI = D23;
const PIN_CS = D5;        // NSS
const PIN_RESET = D21;

// Configuration
const txConfig = {
    bandwidth: 0,
    freq: 434330000,
    power: 17,
    forcePaBoost: true,
};

And the code like this:

// Setup
const spi = new SPI();
spi.setup({ sck: PIN_SCK, miso: PIN_MISO, mosi: PIN_MOSI });
const sx = require("SX127x").connect({ spi: spi, cs: PIN_CS, rst: PIN_RESET });

// HW SPI (replace the three lines above)
// SPI2.setup({ sck: PIN_SCK, miso: PIN_MISO, mosi: PIN_MOSI });
// const sx = require("SX127x").connect({ spi: SPI2, cs: PIN_CS, rst: PIN_RESET });

// Poll DIO0 for interrupts
setInterval(function () { sx.onIRQ(); }, 100);
sx.setTxConfig(txConfig);

// Transmit
sx.send("Hello", function () {
    console.log("TX done");
});

I've attached two screenshots of the SCK, MOSI and MISO, and it looks like nothing is happening on the MOSI line when using HW SPI with this example--I'm sure I just missed something obvious, I hope someone can spot it 😬🙌?

(are there restrictions to the CS/RESET pins as well perhaps? Do I need to set the I/O "mode" for some of the pins manually? Do I need to specify more parameters when using HW- as opposed to SW SPI?)

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