How to use SPI like in MicroPython ?

[AhmedM-Dev]

I am trying to clone the MicroPython NRF24L01 (https://github.com/iottrends/NRF24l01_MicroPython/blob/main/nrf24l01.py) driver using KalumaJS.

My issue is that I could not replicate the exact behavior of spi.readinto using KalumaJS SPI interface.

Can someone guide me how to do it ?

[communix]

@AhmedM-Dev I checked the MicroPython spi.readinto function and I think it can be implemented by the spi.transfer() function of Kaluma.

Both function read and write the data through SPI. Here's the difference.

• MicroPython spi.readinto(buf, write=0x00) function read n byte (length of the buff size) data via SPI and store read data into buff. at the same time, it send "write"(byte) n times via SPI.
• Kaluma spi.transfer(data [, timeout]) function write the n byte data (n is the length of the data) and return the read data.

In this example, the self.buf = bytearray(1), that means it's one byte buffer, so spi.readinfo send and receive only one byte. Here's the code for Kaluma

• MircoPython: readinto(self.buf, reg)
• Kaluma: buf = spi.transfer(new Uint8Array([reg])); // reg is one byte data to send and buf is the read data(byte)

Thanks.

[AhmedM-Dev]

@communix Thank you so much for your well explained reply. I will try to implement the nRF24L01 driver based on the MicroPython driver using your suggestion and send you feedback as soon as possible.

Thanks.