Functional SPI

libraries/SPI/SPI.cpp

+/*
+ * SPI Master library for Arduino Zero.
+ * Copyright (c) 2015 Arduino LLC
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include "SPI.h"
+#include <Arduino.h>
+#include <wiring_private.h>
+#include <assert.h>
+
+#define SPI_IMODE_NONE   0
+#define SPI_IMODE_EXTINT 1
+#define SPI_IMODE_GLOBAL 2
+
+const SPISettings DEFAULT_SPI_SETTINGS = SPISettings();
+
+SPIClass::SPIClass(NRF_SPI_Type *p_spi, uint8_t uc_pinMISO, uint8_t uc_pinSCK, uint8_t uc_pinMOSI)
+{
+  initialized = false;
+  assert(p_spi != NULL);
+  _p_spi = p_spi;
+
+  // pins
+  _uc_pinMiso = uc_pinMISO;
+  _uc_pinSCK = uc_pinSCK;
+  _uc_pinMosi = uc_pinMOSI;
+
+  _dataMode = NRF_SPI_MODE_0;
+  _bitOrder = NRF_SPI_BIT_ORDER_MSB_FIRST;
+}
+
+void SPIClass::begin()
+{
+  init();
+
+  nrf_spi_pins_set(_p_spi, _uc_pinSCK, _uc_pinMosi, _uc_pinMiso);
+
+  config(DEFAULT_SPI_SETTINGS);
+}
+
+void SPIClass::init()
+{
+  if (initialized)
+    return;
+  interruptMode = SPI_IMODE_NONE;
+  interruptSave = 0;
+  interruptMask = 0;
+  initialized = true;
+}
+
+void SPIClass::config(SPISettings settings)
+{
+  nrf_spi_disable(_p_spi);
+
+  nrf_spi_configure(_p_spi, settings.dataMode, settings.bitOrder);
+  nrf_spi_frequency_set(_p_spi, settings.clockFreq);
+
+  nrf_spi_enable(_p_spi);
+}
+
+void SPIClass::end()
+{
+  nrf_spi_disable(_p_spi);
+  initialized = false;
+}
+
+void SPIClass::usingInterrupt(int /*interruptNumber*/)
+{
+}
+
+void SPIClass::beginTransaction(SPISettings settings)
+{
+  config(settings);
+}
+
+void SPIClass::endTransaction(void)
+{
+}
+
+void SPIClass::setBitOrder(BitOrder order)
+{
+  if (order == LSBFIRST) {
+    nrf_spi_configure(_p_spi, _dataMode, NRF_SPI_BIT_ORDER_LSB_FIRST);
+  } else {
+    nrf_spi_configure(_p_spi, _dataMode, NRF_SPI_BIT_ORDER_MSB_FIRST);
+  }
+}
+
+void SPIClass::setDataMode(uint8_t mode)
+{
+  switch (mode)
+  {
+    case SPI_MODE0:
+      nrf_spi_configure(_p_spi, NRF_SPI_MODE_0, _bitOrder);
+      break;
+
+    case SPI_MODE1:
+      nrf_spi_configure(_p_spi, NRF_SPI_MODE_1, _bitOrder);
+      break;
+
+    case SPI_MODE2:
+      nrf_spi_configure(_p_spi, NRF_SPI_MODE_2, _bitOrder);
+      break;
+
+    case SPI_MODE3:
+      nrf_spi_configure(_p_spi, NRF_SPI_MODE_3, _bitOrder);
+      break;
+
+    default:
+      break;
+  }
+}
+
+void SPIClass::setClockDivider(uint8_t div)
+{
+  nrf_spi_frequency_t clockFreq;
+
+  if (div >= SPI_CLOCK_DIV128) {
+    clockFreq = NRF_SPI_FREQ_125K;
+  } else if (div >= SPI_CLOCK_DIV64) {
+    clockFreq = NRF_SPI_FREQ_250K;
+  } else if (div >= SPI_CLOCK_DIV32) {
+    clockFreq = NRF_SPI_FREQ_500K;
+  } else if (div >= SPI_CLOCK_DIV16) {
+    clockFreq = (nrf_spi_frequency_t)SPI_FREQUENCY_FREQUENCY_M1;
+  } else if (div >= SPI_CLOCK_DIV8) {
+    clockFreq = (nrf_spi_frequency_t)SPI_FREQUENCY_FREQUENCY_M2;
+  } else if (div >= SPI_CLOCK_DIV4) {
+    clockFreq = (nrf_spi_frequency_t)SPI_FREQUENCY_FREQUENCY_M4;
+  } else {
+    clockFreq = (nrf_spi_frequency_t)SPI_FREQUENCY_FREQUENCY_M8;
+  }
+
+  nrf_spi_frequency_set(_p_spi, clockFreq);
+}
+
+byte SPIClass::transfer(uint8_t data)
+{
+  nrf_spi_txd_set(_p_spi, data);
+
+  while(!nrf_spi_event_check(_p_spi, NRF_SPI_EVENT_READY));
+
+  data = nrf_spi_rxd_get(_p_spi);
+
+  nrf_spi_event_clear(_p_spi, NRF_SPI_EVENT_READY);
+
+  return data;
+}
+
+uint16_t SPIClass::transfer16(uint16_t data) {
+  union { uint16_t val; struct { uint8_t lsb; uint8_t msb; }; } t;
+
+  t.val = data;
+
+  if (_bitOrder == NRF_SPI_BIT_ORDER_LSB_FIRST) {
+    t.lsb = transfer(t.lsb);
+    t.msb = transfer(t.msb);
+  } else {
+    t.msb = transfer(t.msb);
+    t.lsb = transfer(t.lsb);
+  }
+
+  return t.val;
+}
+
+void SPIClass::attachInterrupt() {
+  // Should be enableInterrupt()
+}
+
+void SPIClass::detachInterrupt() {
+  // Should be disableInterrupt()
+}
+
+SPIClass SPI (NRF_SPI0,  24,  25,  23);

libraries/SPI/SPI.h

+/*
+ * SPI Master library for Arduino Zero.
+ * Copyright (c) 2015 Arduino LLC
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#ifndef _SPI_H_INCLUDED
+#define _SPI_H_INCLUDED
+
+#include "nrf_spi.h"
+
+#include <Arduino.h>
+
+// SPI_HAS_TRANSACTION means SPI has
+//   - beginTransaction()
+//   - endTransaction()
+//   - usingInterrupt()
+//   - SPISetting(clock, bitOrder, dataMode)
+#define SPI_HAS_TRANSACTION 1
+
+#define SPI_MODE0 0x02
+#define SPI_MODE1 0x00
+#define SPI_MODE2 0x03
+#define SPI_MODE3 0x01
+
+
+class SPISettings {
+  public:
+  SPISettings(uint32_t clock, BitOrder bitOrder, uint8_t dataMode) {
+    if (__builtin_constant_p(clock)) {
+      init_AlwaysInline(clock, bitOrder, dataMode);
+    } else {
+      init_MightInline(clock, bitOrder, dataMode);
+    }
+  }
+
+  // Default speed set to 4MHz, SPI mode set to MODE 0 and Bit order set to MSB first.
+  SPISettings() { init_AlwaysInline(4000000, MSBFIRST, SPI_MODE0); }
+
+  private:
+  void init_MightInline(uint32_t clock, BitOrder bitOrder, uint8_t dataMode) {
+    init_AlwaysInline(clock, bitOrder, dataMode);
+  }
+
+  void init_AlwaysInline(uint32_t clock, BitOrder bitOrder, uint8_t dataMode) __attribute__((__always_inline__)) {
+    if (clock <= 125000) {
+      this->clockFreq = NRF_SPI_FREQ_125K;
+    } else if (clock <= 250000) {
+      this->clockFreq = NRF_SPI_FREQ_250K;
+    } else if (clock <= 500000) {
+      this->clockFreq = NRF_SPI_FREQ_500K;
+    } else if (clock <= 1000000) {
+      this->clockFreq = (nrf_spi_frequency_t)SPI_FREQUENCY_FREQUENCY_M1;
+    } else if (clock <= 2000000) {
+      this->clockFreq = (nrf_spi_frequency_t)SPI_FREQUENCY_FREQUENCY_M2;
+    } else if (clock <= 4000000) {
+      this->clockFreq = (nrf_spi_frequency_t)SPI_FREQUENCY_FREQUENCY_M4;
+    } else {
+      this->clockFreq = (nrf_spi_frequency_t)SPI_FREQUENCY_FREQUENCY_M8;
+    }
+
+    this->bitOrder = (bitOrder == MSBFIRST ? NRF_SPI_BIT_ORDER_MSB_FIRST : NRF_SPI_BIT_ORDER_LSB_FIRST);
+
+    switch (dataMode)
+    {
+      case SPI_MODE0:
+        this->dataMode = NRF_SPI_MODE_0; break;
+      case SPI_MODE1:
+        this->dataMode = NRF_SPI_MODE_1; break;
+      case SPI_MODE2:
+        this->dataMode = NRF_SPI_MODE_2; break;
+      case SPI_MODE3:
+        this->dataMode = NRF_SPI_MODE_3; break;
+      default:
+        this->dataMode = NRF_SPI_MODE_0; break;
+    }
+  }
+
+  nrf_spi_frequency_t clockFreq;
+  nrf_spi_mode_t dataMode;
+  nrf_spi_bit_order_t bitOrder;
+
+  friend class SPIClass;
+};
+
+class SPIClass {
+  public:
+  SPIClass(NRF_SPI_Type *p_spi, uint8_t uc_pinMISO, uint8_t uc_pinSCK, uint8_t uc_pinMOSI);
+
+
+  byte transfer(uint8_t data);
+  uint16_t transfer16(uint16_t data);
+  inline void transfer(void *buf, size_t count);
+
+  // Transaction Functions
+  void usingInterrupt(int interruptNumber);
+  void beginTransaction(SPISettings settings);
+  void endTransaction(void);
+
+  // SPI Configuration methods
+  void attachInterrupt();
+  void detachInterrupt();
+
+  void begin();
+  void end();
+
+  void setBitOrder(BitOrder order);
+  void setDataMode(uint8_t uc_mode);
+  void setClockDivider(uint8_t uc_div);
+
+  private:
+  void init();
+  void config(SPISettings settings);
+
+  NRF_SPI_Type *_p_spi;
+  uint8_t _uc_pinMiso;
+  uint8_t _uc_pinMosi;
+  uint8_t _uc_pinSCK;
+
+  nrf_spi_mode_t _dataMode;
+  nrf_spi_bit_order_t _bitOrder;
+
+  bool initialized;
+  uint8_t interruptMode;
+  char interruptSave;
+  uint32_t interruptMask;
+};
+
+void SPIClass::transfer(void *buf, size_t count)
+{
+  // TODO: Optimize for faster block-transfer
+  uint8_t *buffer = reinterpret_cast<uint8_t *>(buf);
+  for (size_t i=0; i<count; i++)
+    buffer[i] = transfer(buffer[i]);
+}
+
+extern SPIClass SPI;
+extern SPIClass SPI1;
+extern SPIClass SPI2;
+
+// For compatibility with sketches designed for AVR @ 16 MHz
+// New programs should use SPI.beginTransaction to set the SPI clock
+#if F_CPU == 16000000
+  #define SPI_CLOCK_DIV2   2
+  #define SPI_CLOCK_DIV4   4
+  #define SPI_CLOCK_DIV8   8
+  #define SPI_CLOCK_DIV16  16
+  #define SPI_CLOCK_DIV32  32
+  #define SPI_CLOCK_DIV64  64
+  #define SPI_CLOCK_DIV128 128
+#endif
+
+#endif
\ No newline at end of file

libraries/SPI/examples/BarometricPressureSensor/BarometricPressureSensor.ino

+/*
+ SCP1000 Barometric Pressure Sensor Display
+
+ Shows the output of a Barometric Pressure Sensor on a
+ Uses the SPI library. For details on the sensor, see:
+ http://www.sparkfun.com/commerce/product_info.php?products_id=8161
+ http://www.vti.fi/en/support/obsolete_products/pressure_sensors/
+
+ This sketch adapted from Nathan Seidle's SCP1000 example for PIC:
+ http://www.sparkfun.com/datasheets/Sensors/SCP1000-Testing.zip
+
+ Circuit:
+ SCP1000 sensor attached to pins 6, 7, 10 - 13:
+ DRDY: pin 6
+ CSB: pin 7
+ MOSI: pin 11
+ MISO: pin 12
+ SCK: pin 13
+
+ created 31 July 2010
+ modified 14 August 2010
+ by Tom Igoe
+ */
+
+// the sensor communicates using SPI, so include the library:
+#include <SPI.h>
+
+//Sensor's memory register addresses:
+const int PRESSURE = 0x1F;      //3 most significant bits of pressure
+const int PRESSURE_LSB = 0x20;  //16 least significant bits of pressure
+const int TEMPERATURE = 0x21;   //16 bit temperature reading
+const byte READ = 0b11111100;     // SCP1000's read command
+const byte WRITE = 0b00000010;   // SCP1000's write command
+
+// pins used for the connection with the sensor
+// the other you need are controlled by the SPI library):
+const int dataReadyPin = 6;
+const int chipSelectPin = 7;
+
+void setup() {
+  Serial.begin(9600);
+
+  // start the SPI library:
+  SPI.begin();
+
+  // initalize the  data ready and chip select pins:
+  pinMode(dataReadyPin, INPUT);
+  pinMode(chipSelectPin, OUTPUT);
+
+  //Configure SCP1000 for low noise configuration:
+  writeRegister(0x02, 0x2D);
+  writeRegister(0x01, 0x03);
+  writeRegister(0x03, 0x02);
+  // give the sensor time to set up:
+  delay(100);
+}
+
+void loop() {
+  //Select High Resolution Mode
+  writeRegister(0x03, 0x0A);
+
+  // don't do anything until the data ready pin is high:
+  if (digitalRead(dataReadyPin) == HIGH) {
+    //Read the temperature data
+    int tempData = readRegister(0x21, 2);
+
+    // convert the temperature to celsius and display it:
+    float realTemp = (float)tempData / 20.0;
+    Serial.print("Temp[C]=");
+    Serial.print(realTemp);
+
+
+    //Read the pressure data highest 3 bits:
+    byte  pressure_data_high = readRegister(0x1F, 1);
+    pressure_data_high &= 0b00000111; //you only needs bits 2 to 0
+
+    //Read the pressure data lower 16 bits:
+    unsigned int pressure_data_low = readRegister(0x20, 2);
+    //combine the two parts into one 19-bit number:
+    long pressure = ((pressure_data_high << 16) | pressure_data_low) / 4;
+
+    // display the temperature:
+    Serial.println("\tPressure [Pa]=" + String(pressure));
+  }
+}
+
+//Read from or write to register from the SCP1000:
+unsigned int readRegister(byte thisRegister, int bytesToRead ) {
+  byte inByte = 0;           // incoming byte from the SPI
+  unsigned int result = 0;   // result to return
+  Serial.print(thisRegister, BIN);
+  Serial.print("\t");
+  // SCP1000 expects the register name in the upper 6 bits
+  // of the byte. So shift the bits left by two bits:
+  thisRegister = thisRegister << 2;
+  // now combine the address and the command into one byte
+  byte dataToSend = thisRegister & READ;
+  Serial.println(thisRegister, BIN);
+  // take the chip select low to select the device:
+  digitalWrite(chipSelectPin, LOW);
+  // send the device the register you want to read:
+  SPI.transfer(dataToSend);
+  // send a value of 0 to read the first byte returned:
+  result = SPI.transfer(0x00);
+  // decrement the number of bytes left to read:
+  bytesToRead--;
+  // if you still have another byte to read:
+  if (bytesToRead > 0) {
+    // shift the first byte left, then get the second byte:
+    result = result << 8;
+    inByte = SPI.transfer(0x00);
+    // combine the byte you just got with the previous one:
+    result = result | inByte;
+    // decrement the number of bytes left to read:
+    bytesToRead--;
+  }
+  // take the chip select high to de-select:
+  digitalWrite(chipSelectPin, HIGH);
+  // return the result:
+  return(result);
+}
+
+
+//Sends a write command to SCP1000
+
+void writeRegister(byte thisRegister, byte thisValue) {
+
+  // SCP1000 expects the register address in the upper 6 bits
+  // of the byte. So shift the bits left by two bits:
+  thisRegister = thisRegister << 2;
+  // now combine the register address and the command into one byte:
+  byte dataToSend = thisRegister | WRITE;
+
+  // take the chip select low to select the device:
+  digitalWrite(chipSelectPin, LOW);
+
+  SPI.transfer(dataToSend); //Send register location
+  SPI.transfer(thisValue);  //Send value to record into register
+
+  // take the chip select high to de-select:
+  digitalWrite(chipSelectPin, HIGH);
+}
+

libraries/SPI/examples/DigitalPotControl/DigitalPotControl.ino

+/*
+  Digital Pot Control
+
+  This example controls an Analog Devices AD5206 digital potentiometer.
+  The AD5206 has 6 potentiometer channels. Each channel's pins are labeled
+  A - connect this to voltage
+  W - this is the pot's wiper, which changes when you set it
+  B - connect this to ground.
+
+ The AD5206 is SPI-compatible,and to command it, you send two bytes,
+ one with the channel number (0 - 5) and one with the resistance value for the
+ channel (0 - 255).
+
+ The circuit:
+  * All A pins  of AD5206 connected to +5V
+  * All B pins of AD5206 connected to ground
+  * An LED and a 220-ohm resisor in series connected from each W pin to ground
+  * CS - to digital pin 10  (SS pin)
+  * SDI - to digital pin 11 (MOSI pin)
+  * CLK - to digital pin 13 (SCK pin)
+
+ created 10 Aug 2010
+ by Tom Igoe
+
+ Thanks to Heather Dewey-Hagborg for the original tutorial, 2005
+
+*/
+
+
+// inslude the SPI library:
+#include <SPI.h>
+
+
+// set pin 10 as the slave select for the digital pot:
+const int slaveSelectPin = 10;
+
+void setup() {
+  // set the slaveSelectPin as an output:
+  pinMode (slaveSelectPin, OUTPUT);
+  // initialize SPI:
+  SPI.begin();
+}
+
+void loop() {
+  // go through the six channels of the digital pot:
+  for (int channel = 0; channel < 6; channel++) {
+    // change the resistance on this channel from min to max:
+    for (int level = 0; level < 255; level++) {
+      digitalPotWrite(channel, level);
+      delay(10);
+    }
+    // wait a second at the top:
+    delay(100);
+    // change the resistance on this channel from max to min:
+    for (int level = 0; level < 255; level++) {
+      digitalPotWrite(channel, 255 - level);
+      delay(10);
+    }
+  }
+
+}
+
+void digitalPotWrite(int address, int value) {
+  // take the SS pin low to select the chip:
+  digitalWrite(slaveSelectPin, LOW);
+  //  send in the address and value via SPI:
+  SPI.transfer(address);
+  SPI.transfer(value);
+  // take the SS pin high to de-select the chip:
+  digitalWrite(slaveSelectPin, HIGH);
+}

libraries/SPI/keywords.txt

+#######################################
+# Syntax Coloring Map SPI
+#######################################
+
+#######################################
+# Datatypes (KEYWORD1)
+#######################################
+
+SPI	KEYWORD1
+
+#######################################
+# Methods and Functions (KEYWORD2)
+#######################################
+begin			KEYWORD2
+end				KEYWORD2
+transfer		KEYWORD2
+#setBitOrder	KEYWORD2
+setDataMode		KEYWORD2
+setClockDivider	KEYWORD2
+
+
+#######################################
+# Constants (LITERAL1)
+#######################################
+SPI_MODE0		LITERAL1
+SPI_MODE1		LITERAL1
+SPI_MODE2		LITERAL1
+SPI_MODE3		LITERAL1
+
+SPI_CONTINUE	LITERAL1
+SPI_LAST		LITERAL1

libraries/SPI/library.properties

+name=SPI
+version=1.0
+author=
+maintainer=
+sentence=Enables the communication with devices that use the Serial Peripheral Interface (SPI) Bus. Specific implementation for nRF52.
+paragraph=
+category=Communication
+url=http://www.arduino.cc/en/Reference/SPI
+architectures=nRF52
\ No newline at end of file