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cmagliecmaglie
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Merge branch 'zero-core' into zero-package
2 parents b16baa6 + cf2be17 commit c3e5bc7

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‎libraries/SAMD_AnalogCorrection/examples/CorrectADCResponse/CorrectADCResponse.ino

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/*
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This sketch easily and quickly finds the right ADC correction values for a particular Arduino ZERO board.
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The correction values that are found are only valid for the board where the sketch is executed.
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This example code is in the public domain.
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Written 6 May 2015 by Claudio Indellicati
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*/
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/*
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How to use this sketch
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1) Remove any connection cable, shield or jumper from your Arduino ZERO
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2) Connect pin A1 to the nearest GND pin using the shortest jumper possible
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3) Connect pin A2 to the 3.3V pin using the shortest jumper possible
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4) Connect the Arduino ZERO to your PC using a USB cable plugged in the USB programming port of the board
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5) Upload this sketch and leave the board powered on for at least one minute
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6) Open the Serial Monitor and press the reset button on the Arduino ZERO
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7) At the and of the procedure you can find logged
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- the offset and gain values for the board where the sketch has been just executed
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- the instruction line to copy/paste in the final sketch
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*/
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#include "SAMD_AnalogCorrection.h"
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#define ADC_GND_PIN A1
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#define ADC_3V3_PIN A2
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#define ADC_READS_SHIFT 8
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#define ADC_READS_COUNT (1 << ADC_READS_SHIFT)
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#define ADC_MIN_GAIN 0x0400
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#define ADC_UNITY_GAIN 0x0800
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#define ADC_MAX_GAIN (0x1000 - 1)
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#define ADC_RESOLUTION_BITS 12
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#define ADC_RANGE (1 << ADC_RESOLUTION_BITS)
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#define ADC_TOP_VALUE (ADC_RANGE - 1)
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#define MAX_TOP_VALUE_READS 10
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void setup()
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{
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Serial.begin(9600);
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Serial.println("\r\nCalibrating ADC with factory values");
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analogReadResolution(ADC_RESOLUTION_BITS);
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Serial.println("\r\nReading GND and 3.3V ADC levels");
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Serial.print(" ");
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readGndLevel();
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Serial.print(" ");
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read3V3Level();
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int offsetCorrectionValue = 0;
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uint16_t gainCorrectionValue = ADC_UNITY_GAIN;
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Serial.print("\r\nOffset correction (@gain = ");
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Serial.print(gainCorrectionValue);
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Serial.println(" (unity gain))");
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// Set default correction values and enable correction
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analogReadCorrection(offsetCorrectionValue, gainCorrectionValue);
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for (int offset = 0; offset < (int)(ADC_OFFSETCORR_MASK >> 1); ++offset)
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{
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analogReadCorrection(offset, gainCorrectionValue);
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Serial.print(" Offset = ");
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Serial.print(offset);
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Serial.print(", ");
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if (readGndLevel() == 0)
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{
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offsetCorrectionValue = offset;
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break;
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}
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}
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Serial.println("\r\nGain correction");
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uint8_t topValueReadsCount = 0U;
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uint16_t minGain = 0U,
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maxGain = 0U;
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analogReadCorrection(offsetCorrectionValue, gainCorrectionValue);
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Serial.print(" Gain = ");
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Serial.print(gainCorrectionValue);
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Serial.print(", ");
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uint16_t highLevelRead = read3V3Level();
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if (highLevelRead < ADC_TOP_VALUE)
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{
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for (uint16_t gain = ADC_UNITY_GAIN + 1; gain <= ADC_MAX_GAIN; ++gain)
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{
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analogReadCorrection(offsetCorrectionValue, gain);
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Serial.print(" Gain = ");
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Serial.print(gain);
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Serial.print(", ");
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highLevelRead = read3V3Level();
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if (highLevelRead == ADC_TOP_VALUE)
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{
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if (minGain == 0U)
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minGain = gain;
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if (++topValueReadsCount >= MAX_TOP_VALUE_READS)
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{
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maxGain = minGain;
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break;
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}
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maxGain = gain;
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}
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if (highLevelRead > ADC_TOP_VALUE)
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break;
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}
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}
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else if (highLevelRead >= ADC_TOP_VALUE)
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{
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if (highLevelRead == ADC_TOP_VALUE)
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maxGain = ADC_UNITY_GAIN;
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for (uint16_t gain = ADC_UNITY_GAIN - 1; gain >= ADC_MIN_GAIN; --gain)
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{
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analogReadCorrection(offsetCorrectionValue, gain);
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Serial.print(" Gain = ");
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Serial.print(gain);
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Serial.print(", ");
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highLevelRead = read3V3Level();
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if (highLevelRead == ADC_TOP_VALUE)
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{
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if (maxGain == 0U)
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maxGain = gain;
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minGain = gain;
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}
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if (highLevelRead < ADC_TOP_VALUE)
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break;
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}
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}
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gainCorrectionValue = (minGain + maxGain) >> 1;
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analogReadCorrection(offsetCorrectionValue, gainCorrectionValue);
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Serial.println("\r\nReadings after corrections");
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Serial.print(" ");
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readGndLevel();
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Serial.print(" ");
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read3V3Level();
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Serial.println("\r\n==================");
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Serial.println("\r\nCorrection values:");
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Serial.print(" Offset = ");
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Serial.println(offsetCorrectionValue);
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Serial.print(" Gain = ");
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Serial.println(gainCorrectionValue);
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Serial.println("\r\nAdd the next line to your sketch:");
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Serial.print(" analogReadCorrection(");
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Serial.print(offsetCorrectionValue);
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Serial.print(", ");
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Serial.print(gainCorrectionValue);
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Serial.println(");");
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Serial.println("\r\n==================");
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}
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void loop()
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{
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}
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uint16_t readGndLevel()
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{
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uint32_t readAccumulator = 0;
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for (int i = 0; i < ADC_READS_COUNT; ++i)
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readAccumulator += analogRead(ADC_GND_PIN);
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uint16_t readValue = readAccumulator >> ADC_READS_SHIFT;
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Serial.print("ADC(GND) = ");
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Serial.println(readValue);
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return readValue;
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}
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uint16_t read3V3Level()
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{
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uint32_t readAccumulator = 0;
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for (int i = 0; i < ADC_READS_COUNT; ++i)
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readAccumulator += analogRead(ADC_3V3_PIN);
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uint16_t readValue = readAccumulator >> ADC_READS_SHIFT;
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if (readValue < (ADC_RANGE >> 1))
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readValue += ADC_RANGE;
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Serial.print("ADC(3.3V) = ");
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Serial.println(readValue);
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return readValue;
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}
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‎libraries/SAMD_AnalogCorrection/library.properties

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name=SAMD_AnalogCorrection
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version=1.0
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author=Arduino
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maintainer=Arduino <info@arduino.cc>
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sentence=Sets and enables the digital correction logic of the SAMD ADC.
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paragraph=Useful to correct the values returned by the ADC.
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url=
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architectures=samd

‎libraries/SAMD_AnalogCorrection/src/SAMD_AnalogCorrection.cpp

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/*
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Copyright (c) 2015 Arduino LLC. All right reserved.
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This library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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This library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
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See the GNU Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with this library; if not, write to the Free Software
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Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#include "SAMD_AnalogCorrection.h"
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void analogReadCorrection (int offset, uint16_t gain)
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{
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// Set correction values
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ADC->OFFSETCORR.reg = ADC_OFFSETCORR_OFFSETCORR(offset);
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ADC->GAINCORR.reg = ADC_GAINCORR_GAINCORR(gain);
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// Enable digital correction logic
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ADC->CTRLB.bit.CORREN = 1;
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while(ADC->STATUS.bit.SYNCBUSY);
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}
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‎libraries/SAMD_AnalogCorrection/src/SAMD_AnalogCorrection.h

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/*
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Copyright (c) 2015 Arduino LLC. All right reserved.
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This library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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This library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
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See the GNU Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with this library; if not, write to the Free Software
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Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#pragma once
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#include <Arduino.h>
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void analogReadCorrection (int offset, uint16_t gain);
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‎platform.txt

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tools.openocd.bootloader.params.verbose=-d2
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tools.openocd.bootloader.params.quiet=-d0
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tools.openocd.bootloader.pattern="{path}/{cmd}" {bootloader.verbose} -s "{path}/share/openocd/scripts/" -f "{runtime.platform.path}/variants/{build.variant}/{build.openocdscript}" -c "telnet_port disabled; init; at91samd bootloader 0; program {{{runtime.platform.path}/bootloaders/{bootloader.file}}} verify reset; shutdown"
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tools.openocd.bootloader.pattern="{path}/{cmd}" {bootloader.verbose} -s "{path}/share/openocd/scripts/" -f "{runtime.platform.path}/variants/{build.variant}/{build.openocdscript}" -c "telnet_port disabled; init; halt; at91samd bootloader 0; program {{{runtime.platform.path}/bootloaders/{bootloader.file}}} verify reset; shutdown"
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