Arduino core for ESP32 Wiki content

Simultaneously use of two SPI buses

In the library is now an example to show the use of HSPI and VSPI simultaneously. Example code created by AlistairSymonds

/* The ESP32 has four SPi buses, however as of right now only two of
 * them are available to use, HSPI and VSPI. Simply using the SPI API 
 * as illustrated in Arduino examples will use HSPI, leaving VSPI unused.
 * However if we simply intialise two instance of the SPI class for both
 * of these buses both can be used. However when just using these the Arduino
 * way only will actually be outputting at a time.
 * Logic analyser capture is in the same folder as this example as
 * "multiple_bus_output.png"
 * created 30/04/2018 by Alistair Symonds
#include <SPI.h>

static const int spiClk = 1000000; // 1 MHz

//uninitalised pointers to SPI objects
SPIClass * vspi = NULL;
SPIClass * hspi = NULL;

void setup() {
  //initialise two instances of the SPIClass attached to VSPI and HSPI respectively
  vspi = new SPIClass(VSPI);
  hspi = new SPIClass(HSPI);
  //clock miso mosi ss

  //initialise vspi with default pins
  //SCLK = 18, MISO = 19, MOSI = 23, SS = 5
  //alternatively route through GPIO pins of your choice
  //hspi->begin(5,6,7,8); //SCLK, MISO, MOSI, SS
  //initialise hspi with default pins
  //SCLK = 14, MISO = 12, MOSI = 13, SS = 15
  //alternatively route through GPIO pins
  //hspi->begin(1,2,3,4); //SCLK, MISO, MOSI, SS

  //set up slave select pins as outputs as the Arduino API
  //doesn't handle automatically pulling SS low
  pinMode(5, OUTPUT); //VSPI SS
  pinMode(15, OUTPUT); //HSPI SS


// the loop function runs over and over again until power down or reset
void loop() {
  //use the SPI buses

void vspiCommand() {
  byte data = 0b01010101; // junk data to illustrate usage

  //use it as you would the regular arduino SPI API
  vspi->beginTransaction(SPISettings(spiClk, MSBFIRST, SPI_MODE0));
  digitalWrite(5, LOW); //pull SS slow to prep other end for transfer
  digitalWrite(5, HIGH); //pull ss high to signify end of data transfer

void hspiCommand() {
  byte stuff = 0b11001100;
  hspi->beginTransaction(SPISettings(spiClk, MSBFIRST, SPI_MODE0));
  digitalWrite(15, LOW);
  digitalWrite(15, HIGH);