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Class

SPI

Name

transfer()
Examples
import processing.io.*;
SPI adc;

void setup() {
  //printArray(SPI.list());
  adc = new SPI(SPI.list()[0]);
  adc.settings(500000, SPI.MSBFIRST, SPI.MODE0);
}

void draw() {
  // read in values over SPI from an analog-to-digital
  // converter
  // dummy write, actual values don't matter
  byte[] out = { 0, 0 };
  byte[] in = adc.transfer(out);
  // some input bit shifting according to the datasheet
  int val = ((in[0] & 0x1f) << 5) | ((in[1] & 0xf8) >> 3);
  // val is between 0 and 1023
  println(val);
}
Description Transfers data over the SPI bus

With SPI, data is simultaneously being exchanged between the master device and the slave device. For every byte that is being sent out, there's also one byte being read in.
Syntax
.transfer(out)
Parameters
out byte[]: bytes to send
out String: string to send
out int: single byte to send, e.g. numeric literal (0 to 255, or -128 to 127)
out byte: single byte to send
Returnsbyte[]
Updated on January 1, 2021 03:38:10am EST

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